Leak At Transmission Fill Pipe on 1979 300SD

So, I filled my transmission after connecting the fill pipe and it leaked (using aluminum crush washers from the dealership). Unfortunately, I had to disconnect and drain the transmission to get the exhaust back on, so I got to install the aftermarket cruch washers from my filter kit. It still leaked. I ran the car for four days and did a fluid and filter changed (used transmission had been sitting a long time). And it still leaks!

I find it very frustrating to get through a transmission swap and be stumped on a fluid and filter change! Any advice welcome. Someone told me that the banjo bolt could be bent, but it is not visibly so, and it worked fine in the old transmission. Maybe I should try the pan from the old tranmission next? Is my technique bad? I never changed the fluid on the old transmission (hadn't had the car very long when it went out).

Any hints welcome. Thanks in advance.