1977 2.7 with fresh rebuild

[npresley]

Got a few questions:
1. I have a set of 1973 heat exchangers I want to install. The flanges are about .250", but the stock exhaust flanges from the '77 exhaust are about 1.0" thick. Is there a trick to install the older heat exchangers? I used a bunch of washers under the nuts against the flanges, and they didn't seal against the head very well.

2. The idle (stock CIS induction) is at about 1200 rpm. Is that normal? Should I adjust it down? How do I do that?

Thanks,

Nathan Presley