Just editing this first post to clarify things a bit. The tubular control arm I used was made by RCC(no longer in business). The only change I made to it was to weld the bracket on that holds the new control rod to the arm. My latest improvement eliminated the need for a connector on the control arm. The control rod now goes directly to the frame, eliminating any movement caused by flexing of bushing material. So the lower control arm you use to make this set up does not matter-stock, tubular WCF or anything other than the Held/Arraut bumpsteer kit.The lower control arm is just along for the ride when you mount the control rod to the frame. The part that I made bolts to the spindle and is not an RCC part. This is a part that anyone with some fabrication skills , a mig welder, metal chop saw, a vice, small drill press and a hand held grinder with a cutoff wheel can make. I do not have drawings for it. This bumpsteer bracket can be used with the stock strut assembly. I went the full monty and made my rear suspension in to a SLA setup but that has nothing to do with bumpsteer. For 84 to 87 Fiero's only.
This was not an original idea on my part .While I was trying to figure out how to make an upper control arm for the rear of my car , I saw Yarmouth Fiero's design for a bracket to hold the spindle in position without the need for the tie rod that GM so thoughtfuly put in the wrong place .Anyway , I came up with a version of YF's bracket and it seems to work .Not tested in the real world yet , but all indications are that it does the job .Using this bracket allowed me to use an upper ball joint and more traditional "A" style upper arm for my build .I think this design could be adapted to a stock lower arm too .The lower arm you see in the pic is an RCC arm , no longer available .Just throwing it out there , more pics can be seen on my build thread in the construction zone .

[This message has been edited by wftb (edited 12-13-2017).]