Bob, we are also blessed to have one of the best Tremec dealers in the country in Standard Transmission in Fort Worth. Lots of the Dallas gang has had theirs worked on there and they are awesome.
http://www.standardtransmission.com/
Jimi Guthrie from Standard posts here under the Transmission Talk forum.
Tell Jimi I sent you and maybe, just maybe, he'll add on your "Miles hassle-factor" pricing for you!
jimig@standardtransmission.com
Here's a good discussion of transmission/rear end gear combo's. Check out the rpm calculator that's linked.
Rear Gear Ratio??
I agree with Francis - I have the 3.73 with the .62 and there is a big drop in rpm from 4th to 5th, but that's kinda the point. A close-ratio 4 speed that will get you through 120 mph with a big overdrive. There's an unhappy zone around 60 mph or so where the rpm's are too low for 5th but I got 20.43 mpg on a 3 hour drive to Austin at 75 mph!
