Ever heard of a Feretta?
How about a Beretta, powered by an Isuzu V8, and a 5 speed similar to the Fiero 5 speed (from the article).

Linky





So reports the Feretta's owner Tyler Pitman, a former Beretta owner who tells us this hand-built concept car drives nothing like any other Beretta. He says it accelerates like an LT1 Camaro with plentiful low-end torque, making a noise that he's had bystanders tell him sounds like a "Winston Cup [stock] car." How much power it really makes, though, remains a mystery, as does much else about the Feretta's one-of-a-kind, all-aluminum Isuzu V8.

We're talking a twin-cam, 32-valve unit, displacing about 3.5 liters—its exact displacement isn't known. It's remarkably complex for an engine in an '80s American car, with coil-on-plug ignition and separate ignition modules for each cylinder bank, whose heads are connected by a belt driving the camshafts from the back of the engine. Being a GM vehicle, though, the Feretta isn't all bespoke; its starter comes from a GM V6, and its alternator, the Isuzu Rodeo. Its attached five-speed manual transaxle also hails from Isuzu, and might be a box similar to the one supplied for the four-cylinder Pontiac Fiero.
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Pitman's goal is to preserve and document this artifact of GM's past, from its one-off body and interior to that impeccable Isuzu V8. That hasn't been easy, as while a hole in its muffler was easily patched and a failed igniter could be substituted for one from an Infiniti Q45, any serious maintenance isn't doable. There's nothing in the way of service literature, never mind parts, so there's no way to fix the Feretta if anything goes wrong, either at random or when Pitman takes it to a dyno to determine its power output. As such, Pitman is on the hunt for GM and Isuzu engineers who have some knowledge of the Feretta, and could help him maintain, restore, and fully explore the most unusual GM L-body in existence.

I posted this here, since there seems to be a great deal of "institutional knowledge" lurking here.
Hey... It has an Isuzu 5 speed (and V8), so that's good enough for me. Could you imagine that, swapped into a Fiero?!
Hope nobody minds.

[This message has been edited by Raydar (edited 08-15-2023).]