Say what you will about Deve, for or against (I have done my share of both), he nailed it on this heater motor swap.
One of the smart things he did was elongating the holes rather than making new ones. This will give you a positive reference for locating the motor to the housing in the proper location. Drilling entirely new holes may lead to the squirrel cage contacting the inside of the housing. The clearance is rather tight.
Carl
