'68 318 to carbed Magnum 5.2: Check my checklist

The downpipes had not been completely welded when I first started the engine. Finished my semi-booger welds tonight:





That said, I have a bit of a quandary going with the ball-end Walker exhaust manifold connectors. These things have thick flanges with no bevel/chamfer at the flange:


(FYI, the pic shows the 2.5" versions - they won't work if you're trying to cross-reference part numbers. You need the 2.25" version, P/N #41725 for the large-flange Magnum manifolds).

Unsurprisingly, I don't have the ball ends centered on the manifolds so that the pipe clears the torsion bar with ease (no matter how centered it looks here, it isn't):



This said, can I rely on the flat flanges to seal the ball end, even if the pipes are not parallel to the manifold? They seemed to be nice and tight during the engine startup, but I can tell you that you'd never hear an exhaust leak running it with those short downpipes.

Should I get a pair of chamfered 2.25" flanges (like the one below) and replace the flat flanges? Honestly, I'm a bit paranoid about getting an answer on this one, for it looks like I've run into yet another one of those unusual little questions that the internet has never answered until now. Seems like everything has beveled flanges except these things from Walker.



-Kurt