OK- - - - -thanks! The rule of thumb to bring the early 235 head up to 848 compression has always been to mill .090" off the early head, and recess the intake valves the same distance to prevent burning the edges of the valves from the flame front moving across the combustion chamber. It sounds like a similar cut on the 261 head might put me in the ballpark, compression-wise. To avoid pushrod length, rocker geometry, and rocker arm adjuster problems, it's a good idea to shim the rocker shaft stands up the same distance as the head is milled, and run a lash cap on the exhaust valves.
Jerry
