Have a big block 727 with a cheetah 17156 reverse manual vb and when i bought the car it had a bad 2/3 overlap. Took it to a mechanic and told him just to rebuild the trans and fix the overlap. When he did he put a restrictor in the trans and it fixed the overlap but every now and then would slip going into 3rd gear at higher power. I assumed that it had a 5.0 lever in it but when we opened it up you could not see the number. I purchased a 4.2 to put in it and when we opened it back up sure enough it had a 5.0 lever in it. Now the 4.2 is in the trans and the restrictor gone. Now it has an overlap again. Originally the overlap was only at lower power/rpm, now the overlap is all the time. The mechanic nor i have any ideas what to do with it. Has anyone ever ran into this problem before and if so what is the fix?