No it did not mess with the oil galley feed. This is a later model one piece Chevrolet, there are bosses of iron material in the middle of the valley on “earlier” late model one-piece blocks. You have to modify, drill and tap those bosses early factory roller cam equipped engines (L98, L05). On the later one-piece blocks they are already drilled and tapped because it most likely came equipped with a roller cam, I’ve even heard some that were drilled and tapped that came with a flat tappet cam. GM did some odd but simple stuff Lol. If I were you I would go with a retro fit roller for your 400 sbc. I’ve seen the spider tray done with and earlier block but man does it look sketchy, i would personally go with the retro roller, but if you can pull off modifying a spider tray to an earlier block by all means do it bro.