Ballpark Gear Ratio

My Duster clone is roughly 3000# w/ me. I haven't had it on a scale yet. 'Glass bumpers alum bumper brackets, glass hood and fenders. Minimal interior (2 Corbeau buckets), no heater, Weld Pro Stars.
It has a 360 w/ ported 915's, 770 vac sec carb, Torker II intake, 292 purple cam, 11.25:1 comp, 1 3/4 headers.3200-3500ish convertor, 26" tall tires and 4.10 gears. (380ish hp?)
I recently got it running, and the rear howls big time.
This driveline came out of a totaled D150, so I have no practical experience with it.
If I need to replace the ring & pinion, what would be close to the "right" ratio?
I tried the Wallace calculator, but I have too many unknowns.