I hear that undersized cam housing bores and bearing scraping is common on mopar big blocks.
And just for reference, my old mega block had the 2nd and 3rd bores .001-.0015 undersized and had to be corrected.

AG.

1970 Challenger w/572 Hemi street car and my pride and joy. 1986 T-Type with 272 Stage 2 Buick V6 engine - True 8 second street car. Just updated the engine and put down 928 HP @ 35# boost to the ground on chasis dyno. 1976 Cee Bee Avenger Jet Boat - 460 Ford powered.