Cyril,
Funny you should mention that. Today I found a local shop that is know for doing custom work on Ferrar'si and Vettes... They say this guy knows how to weld (if it looks like a row of nickels then I will agree).
On the other hand I found some tips but they may a bit to long. It looks like the muffler could go futher back but I need the muffler in hand to get a good look. I should have everything done by Tuesday so I will put up a new post then.
Thanks for all the help!
-marc