TR-6 rear end rebuild w. 4.1 crown and pinion

[gdk@thumper.bellcore.com (Gabor Kiss)]

I have a 1972 TR-6 that needs a rear end rebuild and I figured that if
I have to spend the money anyway, why not get a 4.1 rear instead of
the 3.7 stock rear. The Roadster Factory will do the rebuild for about
$650 but they don't have the 4.1 crown wheel and pinion. Does anyone
know of a source for these parts? 

While I'm at it I may as well ask, is there anyone with an overdrive
unit for sale? TRF will not sell me a rebuilt tranny with overdrive
unless I send them a core. Apparently they are pretty rare. 

                Gabor Kiss
                gdk@thumper.bellcore.com