700r4/rear end ratio

I am building a 48 chevy trk for my Son & I am having a 700r4 trans built for it. It has a 1976 Chevy motor w/a a rv cam, smog heads , dual exhaust & Edelbrock intake,cam & performer intake...maybe 250 hp
The trk has a Ford 9" rear end w/a 3.0 ratio. I also have 2 other punkins available a 3.25 & a 3.7.
My goal is to reduce engine noise, when cruising, w/out lugging the motor. I'd like to have advice on which pumkin to use from those who experience with gearing when using a 700r4...........thanks Don

What size rear tire?

Forgot - rear tire size is 27"
Don

Streets - I know the RPM's each ratio will give, I wanted to know which ratio you would recomment . I do not know if the current ratio(3.0) will give too low of a rpm in overdrive & tend to lug the motor.....if so I'll go to a lower ratio in the rear. The truck is for daily transportation for my son. The overdrive is 0.7.
Thanks Don.

Thanks Street - thats what I thought you would say.......thanks again.

Don, look at this site, www.bowtieoverdrives.com then click on faq's first gear comparison.

I took the 2.90's out of my '93 Vette, put in 3.55's, and it still gets 20 mpg average, plus a nice cruising RPM in OD.

My '34 lowboy is getting 3:73's with a 700R4. Great torque multiplication in low, plus decent cruise.

Thanks Guys - I've decided to go w/the 3.25. That will give me the same final ratio of my 02 Chevy trk & I think will probably give James the best Gas mileage....thanks again