I believe 3200 rpm is about the top rpm you would want to run for a long period. If you build a 235 correctly you could get it to spin in the 6000 and 7000 range, but that would be a race motor and you would be eating up main and rod bearings very quickly. When it comes down to it the 235 only has 4 main bearings and a long wobbly crankshaft. The faster you spin the engine the more wobble you get.
Run all day at 3200, redline at 4000, absolute redline at 4500.
The 235 is not very economical spinning at 3200 rpm, so you don't want to be near there for cruising rpms. I would think you would be happy if your engine was right at 2000- 2400 range at 70mph. That means the 2.73 gears with overdrive will not suit your needs. You would probably want to be in the 3.55 through 4.11 range if you are running an overdrive, but that also depends on the overdrive ratio.
What does this all mean? Give us more info on how you want to use your truck. If you want economy, you would choose higher gears... say 3.55 with overdrive. If you want to use your truck like a truck for towing (doubtful with the selection of a t5) you would use the lower gears like a 4.11. Midrange gears like the 3.73 may give you the best of both worlds. The 2.73 gears would work well without an overdrive assuming you have a steep first gear. It may be hard to get your truck started on a hill with such a high gear ratio. Towing would be out of the question.
