slant six lifter swap

Let's hope not; for reference, my engine was sludged and varnished to the max, so is a rarea case. I've been into a fair number of engines but nothing like this one was. The PO had a gas leak in the carb for years that drained into the intake; he never added oil because the leak just replenished the oil with gas! All that gas in the crankcase caused tons of varnish. (It had 61k miles at the recent rebuild.......)

Lemme know if you want a hand; I am not that far.