Fluid change after trans rebuild
 

Should trans fluid be changed after 500-1,000 miles after a rebuild, as with engine oil after an engine rebuild, or does it not matter for the trans? If it is changed soon for the first time, I'll probably put in Valvoline for the initial fill, then switch to Swepco at the first change.

Yes, by all means ... change the gear oil after 1000 miles, as that is what used to be done at the 1000 mile check at dealers!

Valvoline 85W-140 non-synthetic is what I recommend for breakin.