Just read your thread, and I am amazed,what you have done and reached with your car, quality!!!!
Have you made your decision on the diff?
Would you pls share your experience with it, because my next mod will be this one, for this season!
I have a 197, using it mainly on trackdays at hungaroring (f1 track), slovakiaring.
my mods are similar to yours:ultra racing strut bars front-back, good ridge brake lines, ferodo ds3000 pads, Toyo r888, adjustable top mounts by Simo with 1.2 negative camber in front, Proex exhaust only after the mid silencer