Well, tonight was one of those "DOH" moments - the kind one probably should keep to themselves, but that might also help someone else through the "..what's going on???" moment. I got my passenger side header back first, bolted it on to see how it looked, then took it loose to close the door and mark the cut line for door clearance - a critical issue on suicide doors. The cut line is at 2" from the end, which is OK but quite a bit more than I expected having not measured it before. Tonight I get the drivers side back, bolt it on, same drill, and the cut line is at 1/2"!! WTF??

Now logic says that the passenger side on a SBF is the lead bank, and that head sits about an inch farther forward, so what's going on?? I should have plenty of clearance on the passenger side if I only need 1/2" on the driver's, right?? Well, after looking at it a while one realizes that the heads are interchangable side to side, so the pattern of exhaust/plug/exhaust/plug on the driver's side becomes plug/exhaust/plug/exhaust on the passenger front to back. The back primary on the driver's side is 2.75" from the cowl, while the same pipe on the passenger side is only 1.25", a difference of 1.5" even considering the lead cylinder difference! Now it all makes sense, but it makes it even more critical to consider the total offset side to side relative to the doors on outside pipes, unless they run low beneath the door line. Thought this one was going to make me crazy, and not sure it didn't....