46RH with 3.73 gears and a 25" tall tire will run 2,400 all day long with O/D and lockup engaged.
If looking for that type of cruise capability and a harder launch out of the hole you may want to concider using the A904 based 42RH that you would find behind the same years of pickups and vans but with a 3.9L V6. Drag racers are using the 42RH because 1st gear is numerically lower than the 46RH originally for more grunt with the V6, but works great for racing. The O/D and lockup are the same ratio wise as the 46RH. So the freeway numbers I quoted with the 3.73s and a 25" tall tire like a 225/60R15 would be the same. Plus the 42RH is smaller, and lighter than the 46RH. If built right the 42RH can handle up to 500hp. So for a street build it will be plenty fine.
As far as CR goes I'd say 9 to 1, or 9.5 to 1 should be sufficient for a pump gas street engine.
