On the small block pan, when adding the front horizontal baffle, you'll also need to drill a small ~3/4" hole for the dip-stick to enter. I've also seen small 1/4" holes drilled in the baffles to help returning oil into the sump. The rear needs the baffle to be cut for the pick-up tube to clear it (as shown in the HOT ROD article).
I've had this mod done to my car about 40 years ago (for autocross intentions)... best engine mod ever! Now, with the Milodon road race pan available, that will be the next step to better oil control (and possibly adding an Accusump with remote filter).