A833 early gearset in OD case?

I was planing on putting a Hemi internals from a crash box into an all aluminum OD case with Aluminum tail shaft and side cover. I found out that some of the OD cases I have are different at the reverse detent and switch. I have one that will work. I called Dan at Brewers and he said don't do it. Just use the hemi case, Install the tail shaft and main shaft from the 23 spline. I am taking Dans advise. he said it will be much stronger for big Horse power.