Math is math - assumptions, such as 1:1 final trans ratio, calc tools, not seeing actual formulas and calcs, rounding errors, acurate numbers for variables, multiple variables, etc. is what throws the product off.
What do I think?
I think I missed by a blind calc by 600 rpm, you trust your rearend guy, and have come up with some options - time to make a desicion, sign a check, an let your mechanic start getting dirty. Let us know how it works out for ya.
Cavebull
