[rwhit57]

I've seen plenty of those blocks over the years. The 350 became the workhorse of the Chevrolet lineup and was available in almost every model car they produced. With the dipstick cast in both sides it was one block fits all models theory. If there were clearance issues with Exhaust manifolds, power brake boosters, smog equip., etc. they could be either right or left dipstick locations. Good eye I'm sure a lot of guys have never noticed that.
Randy