Lowest workable rear end ratio with 1950 Merc

[Sixseven]

What is a reasonable rear end gear ratio for the 1950 Mercury 110 hp engine?

The engine is in the station wagon which is geared at something like 4.4/1. I see that possible gear sets can be installed from the low 3's up to my current set. My tires are 28.9-inches in diameter, with a range of rear end gear ratios of 3.0 to 3.8/1 my engine rpm at 65 mph would be:

3.0: 2300
3.2: 2400
3.4: 2600
3.6: 2700
3.8: 2900

I just chose easy gear ratios so actual available ratios may differ. In the evaluation I wonder is the engine can still power through any of these gear ratios. May be that I just want to avoid highways altogether. My current gear ratio calculatres that I am turning about 3400 rpm at 65 mph. I've also contemplated installing an overdrive transmission. That option is not dead, but I'm still working on locating one with all the controls.

Mission: drive to shows, cruise stay relatively local but within a 200-300 mile range, not kill the engine in doing so.