Not much help for you Mike, but I thought it was cool that a similar thread was started ten years ago:
http://986forum.com/forums/general-discussions/3591-maintaining-interior-leather-vinyl.html
Lots of good info will come up with a search. Did you see the tread about the seat recondition yet? (Amazing)
Reconditioned Leather Seats before and after pics
I use
Mink Oil Paste on any places where the leather is loosing its elasticity or getting creased.