Re: T56 6 speed
+2 on what Elky said...only 93 had the steeper first gear but it was a weaker trans. After doing research, most told me that 3.73's to 4.11's were best with the T56.
I'm going to be running 4.10's with mine. Had a TKO w/ 3.73's in my '91Z, 1st was super steep but great for hard launches, cruising around town, I started off in 2nd most of the time.
70 Skylark Convertible Pro-Touring project - LT1 w/ Lloyd Elliott cam, 11.1, 58mm TB, custom harness & tune, T56, 12-bolt w/ 4.10s
87 Iroc, ZZ4, ProTopline 220cc, cc305 w/ 1.6's, Miniram, Paxton SN2000, Raptor 700R4 w/ Vigilante 2600 stall, 3.73's, Hotchkis suspension w/ Koni adjustables, C5 brakes, 17" Centerlines