On to the transmission-found a good donor motor for my 261, its a 235 with the "unknown" (not listed) cast code of 3837161. Another thread said this is most likely a '55. It does have the four bolts for the valve cover so I'm inclined to think thats correct. It came out of a '52 3100, but owner said it was original stock??. I will check date code when it gets pulled. Anyway, a goldmine of good parts-I will list all the extras I have on the Swap Meet.
