Newbie needs help with simple electric boat joystick control/power

I'm building a simple electric boat out of a salvaged jet ski hull and an old trolling motor with directional control.

The plan is to have a joystick controller for simple on and off (ie no speed control) operation AND reversing of current for reverse and steering.

The kicker is that I was unable to find a joystick that could handle the 35 or so AMPs that would be pouring through it.

I understand that I need a relay. So, I did some chatting with the Digi-Key folks and they sold me these two parts, however, I think the relay needs to be a dual pole.

Anyhow, even if I had the correct parts I don't know how to wire up a relay. Below are the URLs of the two parts I bought.

http://www.digikey.com/product-detail/en/1V15F1100

http://www.digikey.com/product-detail/en/CB1A-M-12V

Attached is my rough sketch of how this will layout - ie two DC motors each needing forward and reverse.

I am a complete newbie. Any help or direction is appreciated.

Thank you in advance I'll look for your response.

Lake15