Bbc engine mount problem

[cheap68]

I ran into an issue installing cpp bbc engine mounts. The bottom two holes don’t
Line up. The truck had a 350 and when comparing the stock perches to the cpp, there is a big difference in the crossmember hole location on both sides. With the cpp mounts the holes in the crossmember are not low enough. I’ve already notched the frame for clearance and I’m using the front two mounting holes on the frame. I don’t see any other option than to drill new holes? Any help would be greatly appreciated. Thanks!