"... How about to 3.55? is the change drastic or minimal?..."


I'd call a change from 3.08 to 3.55 drastic. But, 3.55's work good with a 4-speed. The 3.73's will give you more acceleration, but will increase your freeway cruising RPM up to well passed 3000 rpm.

A 3.23 would probably be about the best compromise, if you do a lot of 70mph cruising. I suppose. The late 2nd gens used the 3.23's and 3.42's, with the 4-speed.