Originally Posted by ernkazern
The Pontiac and Chevy engines use the same lines of transmissions. You can swap them back and forth all day with no problem.
This not exatly true, the bellhousing pattern is different, although there are some transmissions out there that will bolt up to both motors.
A motor swap can get pretty involved, especially when things go wrong or little things come up. They can often take much more than a weekend. Do you really need to swap the motor? why?