Thanks for your replys guys...nope, no thread at all exposed. Looks like they need to get drilled out, then I'll probably have to re-tap for bigger bolts....EXACTLY what I was trying to avoid!
Smitty, I didn't even know that you had to hang the pipe right at the balance point...and yeah, it is the same setup that you have.
When I get them out...if I don't completely destroy the engine in the process...I'll try the other retaining method. And yup...it's the red locktite!
Lee