Jim,
You'll need the head casting code and the block casting code in order to confirm if it is a 235 or a 261.
A149 = block date casting code
Jan 14 1959
E154 = head date casting code
May 15 1954
If my interpretation of the date codes are correct, and the holes in the block for the oil lines are smaller than 1/2" NPT, then the block is a 235 block.
Let's see if someone else corrects or confirms my interpretations.
