It really depends on how you “put a bunch of holes in it”? Without seeing your specific geometry and how your holes are arranged, my initial thought would be to make the holes before you offset/thicken the surface. That way, the walls of the holes will follow the surface. Another option is to use createuvcrv, layout the holes in the resulting border, and then re-apply them with applycrv. The you can use the fin command to extrude them normal to your surface. There’s probably oher ways too - but without an example, it’s hard to tell.