i loved the c4 irs/ifs in my 56 f100 so much i put it in the nova, if you can find a set ( i bought the front and rear complete from a teacher in scotland for 500 quid!) it is easy to fit coilovers instead of the glass leafsprings and if you can ally weld then its easy to narrow the rear end halfshafts too, i narrowed the rear 6" so i didnt have to fit flat sided wheels i have 10" rims with 5" backspace, it is very lightweight as its all ally and polishes up good too, the earlier c4 (84-87) is better for rodding as 88 on they got wider and bigger brakes so you cant fit less than 17" rims , mine are 15" still and the brake discs are a third of the cost of 88 and later, i used a us company www.progressiveautomotive.com for info as they specialise in vette stuff (and others too) for rods and musclecars etc,i think my nova is nearly 300lbs lighter than stock due to a lighter front clip and rear end,