Not to be a downer or anything but my first Z28 was an 82' Pacecar crossfire. Cool when the flaps opened. fast downhill, had ta put a cam in at 48k. they are unique but there is a reason GM only made them 2 years. SHAFTS and all linkage hard to keep adjusted and vacuum sealed up. Alas Tuned port with its 50 bolts......still loved them. Both done around 4500-4800. But if your determined they are rare and unique. Right now I'm opting for the 85'Z28 tuned Port setup I've had since 96' to use on a 4x4 Z71 383 and see what happens. But first let me say I've got a bud in Tyler Tx and thats all he does is corvettes. I can ask if he's willing to talk n give you his buis #.