OK guys, I confirmed my suspicions. I checked out a factory 304 Grem and it has those shitty "LOG" style manifolds. They don't have muc for runners to speak of (all ports dump into the log) so they weren't as tall. Because of this, they ended sooner and higher than the Freeflows and don't interfere with anything. The freeflows were made for the bigger cars that had almost 2 more inches clearance on the pass side than the grem/hornets. They are as close as you can come to headers in a stock manifold... One thing is for sure, I'm gonna have to chain down the engine so the torque doesn't cause damage to the manifolds and stuff.. Bart, turns out my driveshaft is 33.5" long from Center-of-U to Center-of-U. I'll let you know when I've updated my site.. hope to do that this week. I took some pics of the flange during/after the install. Cheers