I had to rebuild my rear end last year. I live in South Louisiana, so like you, it rains here a lot. I put an Eaton trutrac and some 373s. I have a 5.7L that is at about 325 HP, and a week and a half after doing the rear end, I blew up the 4L60E. So I had it rebuilt. Jd master rebuild kit, some Corvette survos, and a shift kit. With the 4L60E, it has a low first gear, so I was going to go with a set of 410 gears, but was talked out of that. I also had a set of 342 gears from the factory. I now push 300 RPMs more than before on the HWY than I did before the gear swap. If you go 410-411, your probably will be about 500 to 600 RPMs more driving down the HWY than you are now. As for driving around in the rain, man it's SOOOO much better. Yes, it will spin the tires, but I don't have to take off from a stop, like I'm 90 years old. It will excellirate normally, like the rest of the traffic does, and even a little faster before it starts to spin both tires. As for the install kit, yes that's what I did. I also used a crush sleeve eliminator kit. It takes a little more effort to install, but if for any reason, you need to remove the yoke, you can, and not effect your pinion depth setting. I also changed my rear brake cylinders, and replaced my axel shaft bearings. I wanted everything in my diff, new. It has been dead quite since the rebuild. I got most of my parts from Summit. The total for the rebuild, was $1100. I have no regrets, and the trutrac, will hold a lot of HP. I know a guy who has one on his 1967 Mustang GT 500 Shelby. He is pushing 865 HP at the rear tires.
