A/C pump Conversion

Has any one here converted their a/c pump into a engine driven. and how are you guys keeping the compressor lubed. I got a oiler that runs from the intake and I ran stainless braided line to the tank from the air out port I also ran a check valve on the line and a oil/water trap under the hood and before the tank. but I still seam to get a little oil in the tank. Any help would be awsome.

Thanks Ryan