Can anyone tell me what this distributor was used on? I am trying to replace the dist in my 75 150 but wanted to match up to what is in it now which I think is a duraspark 2 system. I went to autozone and requested a 79 dist for a 302. The distributor they gave me looks identical, but is just a hair to big to fit in the distributor hole. Did they give me the wrong dist, like out of a 351W? I thought the 302 did not change from 75- thru 83?

 

Are you sure about that number? The basic p/n for distributors is 12127 so the number for a distributor should be C9ZF-12127-LA, even that doesn't SOUND like a good number but not sure.
I looked for the basic p/n 1213 and Fords numbers jump from 1210 (wheel trim ring) to 1216 (front outter wheel bearing).
Check the number and let us know.
Also, on the distributor you have, does it go in the hole but is super tight or is it too big to go in the hole at all?
If it is too tight first, check the distributor for any burrs. If there are any file them down. Then coat the housing with never-seize, lubriplate, or similar lubricant. When you're dealing with aluminum/iron, if the fit is tight its not unusual for the parts to gall and seize in place without lubricant.

 

I did some more digging, it looks like the number you posted is the casting number for the distributor body. From what I can gather, its late sixties small block.
The number that will tell you what distributor you have should be on the side of the distributor, just below where the cap sits.
Usually the 12127 part is cast and the prefix and suffix numbers stamped.
A lot of times when they are rebuilt the housings get bead blasted and the numbers become illegible.
This is a picture of a very old distributor but it'll give you an idea what I'm talking about.