I have never used a solar panel so this is all new to me. How are yall running the wires to the feeder box? I have about 3 feet of wire and not quite sure what is best. I thought about placing the panel on the side of the barrel then running it down and to the motor.

Ross our head lease guy has his directly mounted to the back of his feeder box. Not saying its wrong and his works fine is this the best way to run it or?

Best to put wires in some type of conduit or flex to protect. Guys on my lease has had them chewed up by squirrels, coons, birds etc. check out auto supply places.
Can't help on anything else.

Mount it to the south side of the feeder box and put a critter cage around it.

This

X3

And protect the wires from vermin and damaging sunlight. Garden hose, conduit, pipe, etc.

you have been given some good advice here. Depending on your Feeder control unit (FCU) box size I would recommend mounting flush with the box so that there no exposed wires whatsoever. I have built feeders for some time and never had any customer complaints in mounting them in this manner. A picture of them is on my website and facebook you would like to look at it. If you have any questions feel free to call.

http://i175.photobucket.com/albums/w130/bholt0/Mobile%20Uploads/2009-07/Flushmount1_zps5okfx4xm.jpg

Have gone to mounting the panels like in Bholts picture. Just be sure to face the panel South. No issues with critters getting to the wires that way