Swapping rearends, need your input.

If you cant easily and cheaply find an 8 3/4 unit for the 340, the 8 1/4 should last for awhile. Weve been using an 8 1/4 behind a 360 strip/street for some time. Both of the previous viewpoints have merit. Id recomend to put that 727 behind the 340 when you change things over..... the stock 904 would be marginal, but make the most out of what you have and the 904 would live a long life behind the daily driver 318.