Freeze Plug Size

I searched the site and see some discussion regarding freeze plugs, brass or rubber etc. However, I have a 73 CJ5 with AMC 304. After removing the exhaust manifold I see that 2 of my freeze plugs, are "weeping" or leaking a little. I was thinking now is the time to replace them. When searching the American Motor Parts site I see that there are a couple of different sizes, 1in, 1.5in and 2in. Which on is the correct size metal plug for my 73 304?

 

Can you measure the ones in the block...just to be sure?

 

yeah thought about that, I was gonna try to order em last night, to dark to measure I will put a tape on them this afternoon, thought there may have been a standard size

 

The Dorman catalog may tell you ... http://www.dormanproducts.com/

No time to look it up right now.

 

Measured mine this afternoon 1.5 inches, if this helps anyone else.

 

Coincidentally, the same size as the access holes to your intermediate windshield wiper linkage.