How do you replace the input shaft bearing on FM146?

You have to be able to pull the old bearing and replace it with the input shaft in place (it takes a special puller and installer). Not being able to do that (like me), the transmission needs to be almost totally disassembled to remove the shaft/bearing from the case. There are clearance issues with the countershaft and mainshaft that cause this. If you go that way you still need a bearing splitter and press to get the bearing off and press the new one on. Because you have taken the front cover off the transmission, you will have to do some shimming between the case and outer bearing race.