t3 are too long and the shock is too soft.
ive seen fc used but the upper perch arrangement was pretty ghetto. could obviously be improved upon with some custom parts.
the problem is there isnt really enough room in the turret and the spring/hat etc will foul on the body.
you can have them made on order through GAB a uk company. gilly was having them made and calling them his own but really anyone can order them, you just need to know what to ask for - pin top at the correct length, eye bottom correct i.d, correct stroke/overall length.
i modified my last 86 chassis/diff to fit a universal fit motor sport coil over.
i couldnt say for sure if it was the coil over, or the 4 link (both probably) but that car had by far the best rear end set up ive ever had.
i.e i think rear coilovers are worth the trouble. the only reason id run the normal set up is it looks more factory, so youre less likely to get a defect.