Another 440 4x4 4.10 axle 3/4-ton build: I put the idea together for a friend.

KB 184 with squish set at 0.040
Measured 9.5:1 compression with the 452 heads.
The above took a little juggling and extra work by the machinist but he seemed to be into it.
Hughes cam HE1423BL.
Perf RPM intake
Can't remember the carb
Headers

Mileage in everyday driving jumped from 8 to 15. The truck would run on midgrade, he didn't want to try regular but it probably would have been OK. This guy was ecstatic, it about doubled his real horsepower, too.

R.