That sounds about right, the transmission type doesn't matter, all are 1:1 final drive, rearend and tire size determine engine rpm at any given speed. I've got 3.08's and at 55 I'm just under 3k but with 235/60 R14's on the back.
Only way to improve is taller gears in the rearend or an overdrive unit to change final drive ratio.
Trans does make a difference if you consider a non-lockup convertor. Non-lockup will have some "slippage" and that adds rpm. See my previous post.
BTW, the above numbers don't make sense for your combination. You should be around 2250rpm, or if a non-lockup TC about 2400rpm (or you have a very liberal idea of "just under.)"
