So I picked up a trolling motor off of craigslist for a steal.  Only catch is that the power cable was cut.  12v.  Two wire (red/black).  To attach a plug to the end for a receptacle, is it just a matter of adding the length of wire I need and connecting to the plug?  I would imagine so, just want to make sure before hand.  I've never used one of the plugs and was curious.

Yes, use #10 wire if it is a short run of 5' or less. Use a larger wire for a longer run. Make sure you get a solid connection in the wire splice.

If it is a foot control motor, just replace all of it from the pedal terminals to the plug. Less chance of resistance due to a bad splice.

Yeah it's foot controlled.  I was just looking at it and realized how easy of a connection that is.  Problem solved.  I'll probably use 6 or 8 awg wire for it.  The battery is at the rear of my 12' jon.

Out of curiosity, how good are those plugs?  I swear I remember somewhere that those things are notorious for having power loss with using them.  Be better off just running wires directly to the battery?