this photo shows a plug just left of the front cylinder. I accidentally poked a hole in mine. Any one know of the exact size and where i might find a replacement? Looking for one for 1956 324...

 

I'd try Ross Racing.

 

If one plug was rusty enough to "accidently poke through " then it's time for a whole new set ;
http://www.fusickautomotiveproducts....sp?number=FPK1

 

What he said, and I don't think they are anything that special. Take one to your local parts house and see if they have a set... Tedd

 

I'm a year late on reading your post, so would imagine you've already corrected the plug problem. I had my block cleaned, bored, etc., but found these same plugs to be original to the engine and about ready to leak like crazy. I'd like to know why the machine shop didn't replace them since they replace the other expansion plug. At any rate I found the plugs by size and the NAPA store where I work and put them in with no trouble. Sure am thankful this problem was caught at rebuilding time and not a year down the road. But now I'm finding that it seems the oil gallery plug was left out - didn't learn this until the engine is back in the car and I've tried to prime with no oil pressure Tedd Thompson, who blogs on this site, told me about the gallery plug foul up. Once I find out that this is, indeed, the problem I'll be posting on here so other folks will be forewarned.