There is a reason that when Chrysler started using 2.76 or 2.45 gears in economy cars they also produced Torqueflites with substantially lower 1st gears and half that amount lower 2nd gears... When I installed the 42RH in my Dart I was surprised how much difference those lower trans gears made.
i had both a 77 aspen and 87 dippy, the aspen had a super six and the dippy had a 360 with a TQ. in an impromptu stop light race the two were near dead even, that low gear 904 can be real beneficial in the right set up.