So I was having difficulty installing the driveshaft because it would contact the IRS differential. I ended up needing to lift up the engine to get it installed. I got it all bolted down and even the driveshaft safety loop installed, when I looked at the inventory list that FFR sent stating that the driveshaft they sent me was a 31 spline 9.25". My original order form listed a driveshaft that was 8.375". Oops! Did they send me the wrong driveshaft? Do I need to take it all out? Those bolts now have blue loctite on them... Here are the photos below. I have a Blueprint 427 with IRS. The gap on the yolk is about 1/4 inch. From what I have read, that should be more like 3/4 - 1 inch. If my only problem with this setup is that I would need to lift the engine again if I have a problem with the driveshaft in the future, then I may just leave it alone. But if there will be interference problems with a gap this short, then it would make sense to correct it now.
Thanks for your advice on this!
-David