Hey Mark,
Drivetrain is the following:
79 2F motor with TBI and DUI distributor, stock intake and exhaust manifolds.
Sm420, mini reduction box (Marlin Toybox), to an OTT/Inchworm D300 adapter to an Atlas II (3.8) shafts by Jesse at HighAngle to the HP D60's (RockCrushers) with 4.56 and detroits. Transfered to the ground via Robby Gordon beads, ajnd 37x12.50x17 Red Label Krawlers.
The tcase of choice was Marlins newest creation, a rear disconnect Toy case, but it won't be available for a while. Had to have front dig, so the Atlas was the next in line.
Ratio: 7.05 x 2.28 x 3.8 x 4.56 = 278:1
As far as gear choice in comps, the obstacles dictate the desions. 278:1 is too low for anything around here, except the dryest of rock. Shifting a 420 while getting it doesn't happen, ever! More common is to grab the mini box lever and go to 1:1 for quick shifting wheel speed. Starting in the right gear makes a lot of difference, and thats a feel thing. But, when BigDude says "get it", he really means see if you can get air before it breaks something!
Thanks for the comments all. I snapped a few of it all cleaned up after the last trip out, I'll try and post em tonight.