So now I found a casting code - 3701946. That translates as a 1953 235 engine. How that goes together with the HAA prefix is a mystery to me, unless the H is an L. But It sure looks like an H, and that area is clean and easy to read. Maybe the casting number agrees better with the other aspects of the engine.

It may not be the easy way, but it is the Cowboy Way - Ranger Doug
Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri
1953 Chevy 3100
1960 Volvo PV 544
1941 Chevrolet Special Deluxe