Thank you for your insight. I had also thought of this and returned everything to stock for testing purposes (everything accept the bearing shields that I drilled for added lubrication). The issue remains constant. I believe, due to the port shape, there is less fuel oil mix going into the lower case, as it is bypassing it, going straight from the intake to the transfers. This would explain the short seal life. I also believe that the bearing shields acted as a buffer for crankcase pressure/vacuum, which are more extreme on these engines due to thicker crankshaft, no reed/less case volume. This would explain why some are able to run without shields while others can not. I will test the viton seals and let y'all know how that went.