Speedo Correction: 4.10s & 33 \" tires I've got an '87 with 33" tires, 4.10 gears, and 700r4 tranny. I've done some rearch and the best I can tell, I need to put a gray (15 tooth) drive gear and a red (37 tooth) or blue (38 tooth) driven gear. Here's where I got my info. GM Tranny info I'm I right on my calculations? Anybody have any experience in do in this?