Heater blower motor ID help

[70cuda50]

I ordered blower motor for 70 Cuda non a/c. Obviously some big differences in looks but more importantly the shaft for cage is longer and holds further out from motor so it rubs on inside of housing. The cage I took out of it is plastic...is it even original? I have only seen one picture of disassembled heater box on a very detailed (supposedly accurate) restoration and it had metal cage as well as same style motor and wiring as one I removed. Seems like later models have the extended studs out front of motor in engine bay from most of pics on web. Is this the wrong, later model part? No parts numbers I can see on either. New one came in clear bag with “Genuine Parts” and Mopar symbol printed on it but no identifying info.
I disconnected heater decades ago because was leaking. I think motor was working then but figured replace 50 year old ( 34 since I’ve owned it and it last was used) so I don’t have to tear apart fresh rebuilt box if it is bad. Thanks

 

[Rich G.]

That looks like a universal motor that I guess you can make work if you had to.

 

[moparlee]

The cages are plastic. Don't assume the original motor is dead, put 12v's on it to see if it runs.

 

[Chryco Psycho]

won't look right at all sticking through the firewall . often you can just disassemble the motors , clean them , make sure the brushes slide free & put them back together