Does anyone have a recommended place to have some electronics installed and a out board motor tuned up in the Gallatin/Hendersonville area?

With the help of a friend I tried to put my own electronic on because it seemed simple enough ... Only 2 wires right. Well Murphy showed up and I have some need of help with regards to intermittent operation of my trolling motor and depth finder. I know its a connection that we made but in an effort of keeping this short I don't have the tool or connector (larger one) to make the connection that I think is bad. I took it to a boat place in Camden and they used a vice to crimp it . I don't think that worked well but they didn't charge me because I think they knew they botched it up. So I want to take it somewhere that can do it right and I can focus on fishing. I knew I should have run a line to the fuse box...

Only thing wrong with my motor is its hard to start... and idle might be set to low.

Thanks