Re: Pilot bearing fit
 

It sounds like you either have the wrong bearing or the one you have is undersize.

Do you have the old bearing?

You could go to your local friendly bearing supply house and ask for a 6203-2RS bearing. Don't forget to wear a mask and gloves.

Re: Pilot bearing fit
 

It seems as though you may have the wrong input shaft. I don't know much about the early cars, maybe they had used different shafts and bearings.