I think you will run into a problem here. Both the Orinoco and all GPS cards I have seen, have bulges at the end. So I don't think they will both fit in the expansion pack at the same time. I think your bast bet is going with a garmin unit.

I will be ordering the parts I need later this week to connect my E-Map to my 3870. I am planning on one cable that plugs into the 3870 on one end, and the emap on the other.

Anyone out there with what a useful length of wire should be? Thanks

Dave