That last nut ended up coming out with the help of my new variable speed dremel. Of course, thanks to my brother's pre-holiday present. Thanks Bro! No wonder why he told me to hold off on the header install. It's not a necessary tool to have as part of the installation, however in this case....boy, was it ever handy!
So, I guess the one note that may be helpful would be to first remove the small weld that is located at the top of where the nut and flange actually meet (cat end). Otherwise, it's a bit challenging to get a good hold of it with an open ended 13 mm wrench while using a ratchet
(connected to a 13 mm socket )on the other end. I ended up stripping it.
(Note: this is a M8 nut & a single M8 mm bolt accd'g to the 1997-2004 Bentley Service Manual. There are no other bolts of this type that have a small weld b/w the flange and the nut located at the cat end on either the driver's or passenger's side on a 1999. The other studs / bolts are heat pressed to the flange).
Also, when putting the headers on (at least these headers), it may be a good idea to get the two end bolts in first, but not too tight. Just so that the gasket lines up well and you have the correct fitment; although just to get a bolt or two in there to hold it up may work just as well. The headers get heavier and fatigue starts to set in when carrying them overhead while lying on your back.
Anyway, that stubborn nut is off and the headers are installed. I still have to make an appointment with my local Porsche mechanic to take care of the leaks from the broken studs and bolts. But, I will have to do that once my header wraps come in so that I don't melt my AC line. Other than that, it was a very cool experience!!
Will post some pics as soon as I can if anyone is interested!! :dance: