There is a gasket under the adapter plate, part # 40-389 1107. It's easy to get to, just remove your spin on filter, get an 1 1/8 socket and turn the adapter stud out of the middle, and then remove the plate. You can then take out the old gasket and put in a new one.

I just did this to a 2150, and was having trouble, even with new gaskets, so I put 2 in under each plate. The extra thickness took care of the problem. Also, watch out for revving the engine up too fast or much when they are cold on the 2050 and 2150s. They can create some really high oil pressures, especially if the relief valve hole through the block didn't get updated. The pressure spikes can cause your gaskets to fail, and blow the seals out of the turbo on the 2150. Once everything is warmed up the oil is thin enough that the problem goes away until it cools off again.