I've been running a newly modified super six set up in my '71 Sweptline since Monday with no complaints. I'd like to thank Reed Speir for his excellent article and Doug Dutra and Dan Stern for the info on manifolds. Once I found a kickdown linkage and a cover for the little emissions/vacuum stove in the exhaust manifold things went together pretty easy and it's running fine.
I still need to run a bigger exhaust, but I'm noticing more available power, smoother running, and it gets up to speed a little quicker. Once it is up to speed, it rolls along fine.
Thanks for a great site and excellent detailed info,
Joe