Here is a pic of an 88 coupe front spring (1 coil removed) installed on the rear of an 88. The bottom fits without issue and for the top I retained the stock hat and cut out a circle (about 6" diameter) to rest inside the stock spring hat, cut a hole for the strut and welded on a short piece of 3" exhaust pipe to keep the spring centered.
I did this because I wanted a slightly stiffer rate in the rear. Stock is in the 170 range and an uncut 88 front is about 201. Cutting 1 coil increases the rate to about 235 lb/in, so that is about 38% increase in spring rate. This will also have the car sitting close to a stock level, maybe slightly less.
In the pic, the Blue 88 has a SBC/Getrag and the front springs in the rear (and H&M lowering springs for a BMW in the front). The Red 88 has a 4.3/4T60 and is sitting on stock 88 4cyl/5 speed coupe springs.
I know I could have built coilovers and accomplished the same result, but this mod was free. I have since scored a set of adjuster sleeves so the Red car might get this set and the blue car the coilovers.
