Rebuilt starter out because it was not working

I bought the car about 3 weeks ago, and the seller said that they took the recently, (last year), rebuilt starter out because it was not working. I took the starter to Autozone to have it checked and it worked fine, (not as strong as a new one, however). There were no starter bolts or shims with the car. I remembered that when I replace the starter on my 63 Catalina back in the 60's that there were shims. I bought the bolts and shims at O'reilly's today, but the oldest manual I have only goes back to 1964; and the instructions don't include any particulars about the shim size.

I need to know what size shims, or how to determine which size shims, need to be used, to install a starter/solenoid in my 4-door 1963 Pontiac Bonneville 389 c.I, that was out of the car when I purchased it. Thanks.