Hey thanks for the response. I'm an old hand at using HiFi Engine and I found that their B16 service manual was the most informative. I have an 8090 remote that works perfectly and the pinouts are 1 to 1. Unfortunately, the 4050 is laid out differently. Pin 20 isn't used and 24VDC isn't on pin 5 as with the B16. This is an input to the 4050 and I don't want to damage anything. I have an additional interface document section that describes the 4050 pinouts in great detail. I have spares for both units so I'm good there. There are 8 to 10 pinouts that are described differently for the B16 and 4050, so it's a little frustrating. You probably know how difficult it is to crimp a 40 pin connector and find you need to change things. Oh well, as with all old analog equipment patience is the key. I'll check out the E16 service manual on HiFi Engine, but I'm pretty certain the B16 used the 8441 cable format and the E16 used the 8440 cable format. Never know though.