While you are tring to drive a Gear on While it is in the Motor you run a VERY LARGE RISK OF Knocking out the freez plug in the back of the Block THEN YOU WILL BE Pulling the Motor Or Tranny OUT for sure. And if you Press the gear on without Heating it. IT WILL come OFF soon sometime down the Road IF not shortly after firing it up.So Notto be Rude or nasty about But Pull the Motor and DO IT the RIGHT WAY. you'll be happier in the long run.
Because if that Gear walks off the end YOU will end up trashing the CAM, Lifters, Dist gear?? and Maybe EVEN THE BEARings. So go a head take a short cut if you really want to. But this is/was a fair warning!!!!