I will post it here, as this thread has a lot of interesting information that is still relevant.
I have :
53181A Option 010 124 SN: KR9120XXXXX Made in Korea
53132A Option 012 SN: 3546AXXXXX Made in USA
I wanted to move the 12.4GHz card to the 53132A, but I 1, cannot find the R334 on the 53132A, I did find it on the newer 53181A near J6
I tried it, and the Channel 3 can be selected, but there is no counting being done on the Channel 3. Any idea of the pin or signal jumped By R334 ?
Oscilators : This might also be of interest:
Option 010 Crystal 10811-60160
Option 012 Crystal 10811-60211
Jumpers are at the same place, and board seems to be the same. So I guess that someone with a 010 can find the 012 oven alone and make the swap pretty straight forward.