I didn't think I was old, yet. And my qualities average out to be undesireable, so better try another marketing approach. Some Gen 2 had the cast manifolds as well.
The "kit" should include the bolts. As we all know, the Gen 2 guys are shorter than the Gen 1 studs. (They are shorter than Gen 1 because the flange is thinner.) You also need the V-clamps and stubs of the down pipes to make it worthwhile. Then the only fabrication is connecting 2.5" pipes.
Even so, the buyer needs to cut the bridge pieces between pipes. The Gen 1 head bolts get in the way. The Gen 1 heat shield can be re-used. It is basically a layer of foil, cardboard, and foil so go ahead and bend it to remove and reinstall it. Try not to tear it.
I did it for the weight. Whether it adds power depends on who you ask. But 20# off the front was worth it to me for the autocross benefits. See here to rub it in:
http://www4.forum.viperclub.org/showflat.php?Cat=0&Number=708558&an=0&page=0#Post708558