Rad and m/c questions

[mr57]

I finally got around to doing some work on my 64 swb panel and yanked the rad and master cylinder I know the front clip was swapped out for a GMC sometime in the past, but when I pulled the rad I noticed it was still in the 6 cylinder position. The bottom mount for the V-8 is still there, but the top plate is missing. This isn't a big deal, really, as I can find a V-8 top piece fairly easily, and/or get a shroud if needed.

The question comes in with the rad. I stripped out the drain bung and need to get it repaired, plus get the rad cleaned and pressure tested. If our rad guy can't repair it or it blows apart, is there any difference between a 6 cyl. automatic rad and a V-8 auto rad??

Next question deals with the m/c. The parts guy I talked to says there are four different master cylinders listed in his computer for 1964. It's the fruit jar style, not the square one, for a factory V-8 auto truck. Any idea what the part number should be?? Or am I going to have to rip it apart and measure the bore to find out??