transmission problems

Anyone have a good source for a 4 speed muncie for 1964? I have a cracked tranny case - or is it repairable? I was told that the the crack was caused by re-installing the tranny incorrectly (using bolts as guides?) and it caused the crack that was filled with a silicon or something.

First off hi guys new to the forums. Im currently having issues with my 69 El Camino. Im running a 350 with TH 350 tranny. The car is currently having issues shifting from 2nd gear to 3rd. First off I have changed the modulator with no effect even after adjustments. Here are the symptoms. 1-->2...