I just went through the trans and installed 36 element sprag and drum. Trans go shift kit with the stiffest springs. red alto clutches and kolene steels. All seals, bearings and bushings new. TCI aluminum deep pan. Something broke inside it today. I be I don't have 100 miles on it. Started to slip in second gear and I'm blowing through 3rd pretty easy. I stopped and was close to the house when this happened. Question is should I stop now wasting money on the 350 and go to a glide or 400? Its behind my 421 sb that's making 600 hp at 6700 rpm's and 530 ftlbs of torque at 4800. I am running a 8" PTC converter with a 4500 stall. I was told to stay with a 3 speed auto because of the car seeing street duty. I am interested to see what failed. Hopefully this week I can at least get it out of the car. I have lost damn near all motivation since building this car.