1960s Wrong generator?

[dbzsjones]

I'm restoring a 1961 Series 62 Cadillac and adding A/C from a 1962 doner car.  I mounted the generator,  and when I tried to screw the front lower bolt into the mount on the exhaust manifold I realized the hole in the generator was threaded.  I thought this was the 61 or 62 generator, but now I'm not sure.  Can I drill the threads out of that hole and use this generator, or do I need to go generator shopping?  I can't find a oval metal plate with a part number.  All the markings are in the photos.
  I know for an A/C car I'll need a high amp generator, but it will be a while before I get the A/C In and running so I can make due with either version for now.  Thanks for the help, Del

[Clewisiii]

I like pictures. The pulley also looks like it might be the wrong size.

[Clewisiii]

I had been thinking about buying this from ebay as a spare.

[dbzsjones]

It does look like my pulley is bigger.

[dbzsjones]

I was the 1 watching, and the seller just sent me an offer, so I bought it.  Thanks for the help.