Don't count on that Even tho they work and give right pressure...

I've some intermittent problems that act like something gets hot and won't run. I had spares so slowly swapped many electric parts and still have same problem...

Finally made 15psi (Duke only need 9-13PSI) Fuel Gauge w/ long hose and problem is no pressure even tho pump runs.
People know if drop the tank for any reason just replace the pump and J30R10 hose so yes I got a new pump,

I don't think the pump is dead but...
Hose at top had rust where hit metal feed tube likely loosing some pressure.
"Sock" at bottom of pump was completely F'd. Bad dirt plus was whatever fabric was "rotten" too and failed where has metal part to mount to pump. I think some crap got thru there causing low/no pressure intermittently even tho pump runs. Restricted Fuel Flow for any reason can make FP to run hot too.

I also clean the plug at the "Flange" at top. Mine is ok. That is a plug and socket Not an 1 piece pass thru thing. (Someone found replacement but can't find the post.)
Clean C502 too. Note is a Weatherpack but Not a Generic shell. If pins are iffy can replace them.
Use Plastic Friendly electric cleaner. Cleaner/Lube for externals like C502.

Cleaned Fuel Gauge sender... You can carefully pry up 1 and loosen other 2 "pins" holding it together to clean. I just use "scotch-brite" to knock of loose crap. Is a spring inside to help ground the arm that maybe gone causing problem for many people. When you reassemble make sure all "pins" are tight. Sender should read near 0Ω empty 90+ Ω full. Caution: When tested by hand may drop out when moved because may load sideways and not notice. Note: If this has burn out, Gauge has problems and will fry replacement too.

Dropping the tank... The 2 nut for the straps are locking type and will not "spin" off or on. Clean the Threads before removing them. Dremel w/ wire brush (flat type) save time.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

30 years is amazing for an electric motor that's probably used more than any other motor in the vehicle. Even the saran sock deserves some credit. You didn't mention mileage, just curious. Perhaps fuel pumps in the 80"s were better designed to outlast the vehicle itself. Don't forget to write GM a letter of appreciation, lol..
Spoon

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"Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut

Question, what is the best pump to buy ? I’m at the point that the tank is out, found out the baffle is falling apart….too bad because the tank is clean as a pin inside……so waiting for Rodney’s tank to be available.

~230,000 miles.
While miles might affect the pump, miles matter much less to the sock and other parts.

Most Socks have chemicals besides gas that runs the engine trying to "eat" them over time. Like cleaners in pump gas requires by EPA rules or meet "Top Tier" that many Brand are members. Then many people add more cleaners, "octane boosters" etc. that can hurt soft parts too. On top of ≤10% Ethanol.
Many low mile per year cars have varnish and related because even non eth gas degrades sitting in the tank. Staybil etc only helps some.
"Barn Finds" often have worse problems as gas evaporates...

Guy near me have car in a garage for decades likely have major problems w/ fuel, coolant and brakes.
Idiot next to me has 2-3 vehicles parked outside for few years now and did nothing to protect is likely going to have problems if drive them again. Old carb engines can still "rot" many fuel parts.

I sell pumps mainly water but other uses but quite often i will explain the lines need cleaning etc and sell another pump only for them to try and return it after they tested and finally listened even though i am clear it is required especially if they try tell me losing power when empellar unworn and thermal overheat.

Most Electric Fuel Pumps like Oil Pumps are Positive Pressure/Displacement types and All use Fuel at Coolant flowing thru the motor.
"Small" crap getting thru a iffy Sock or blocked flow can and often will cause Pump Problems or Destroy them. This is Why most FP Warranties require a New Sock installed at same time.

Water Pumps for Vehicles are Not Positive Displacement types will let even a lot of big crap thru w/o them notice ever there. While hate being Running Dry, does no damage w/ crap passing thru or even flow blocked. "Rubber" hoses can collapses etc but do no real damage.

Positive Displacement types are Gear pumps, Piston pumps, and some others. Example: Most Fire Pumper Trucks are this type too. While Building/Fire Codes require various "Stand Pipes" outside of large buildings, many Fire Pump Operator avoid use them because "people" use the pipes as garbage cans causing truck and other damage. Even w/ pipe guards on them, many don't trust people installing them to properly flush the pipes.

FP has second problem because as stated above, Most E Fuel pumps use Fuel as Coolant and Lube. Block flow will cause pump overheat and destroy them. The Regulator in a Fuel Rail or TBI flows a lot of extra gas to set final pressure but also to help FP to cool and lube itself.
New cars w/ only feed line to the engine just moves the Regulator and Return to Near or In the Tank to reduce heating from the engine that cause more EVAP Emissions.

It took 2 days to drop the tank because of rust on parts needing "oil" to work and other reasons... Then more time to check/clean connectors etc. Maybe I could replace just the hose and sock then Hope it fix intermittent problem that forces me to waste Hours to drive home again. Or worse have to Tow because completed dead next time.

System pressure before was 9psi at the bottom end of range.
After is now 13psi as TBI Regulator does its job.

Notes:
700 TBI for 87-88 Dukes can run until has ~ 5psi. I pull pump fuse to release most pressure to do any work on it and watch gauge this time running the engine a bit.
Don't flip out watching a gauge after pump replacement etc. until engine runs a bit. Pump Check valve and Regulator doesn't work right w/ air in the feed line.
Do Not leave Test Adapter in the system. See https://www.fiero.nl/forum/Forum2/HTML/146121.html