Help opinion's needed!!!

If you're still using the stock exhaust manifold, the Offy would be the one as the Clifford doesn't have any provisions to mate with a stock exhaust manifold. If headers, wouldn't matter but I'd probably still go with the Offy.

EDIT: Neither the Offy nor the Clifford mates to your stock throttle /kickdown linkage. You'll have to do some fab work but it's not that big a deal