You will probably have to modify it quite a bit.Expessially the drive.some of the 620s run off the mule drive underneath tractor and some off the side.I believe the 1650 runs off the electric clutch on the front of the motor.Mounting will need some fab work also.Good luck and keep us posted.
The 620 blowers were made for the Massey Tractors mfg by AMF. These were the numbers 10 & 12 specifically. There were actually 3 different versions of the 620, one was mule drive and the other two were direct belt drive.
The later Massey units were made by Snapper and Ingeraoland used a completely different hookup and drive line. You will have to make quite a few modifications to the blower, your tractor, or both.