12V / 24V Compressor

Okay, heres my problem. I just purchased a Electric Compressor for my air ride. It can run at 12V or 24V. At 24V it runs nearly twice the speed, thus faster filling time in the air tank. Anyways, I want toi know if there is a way I can run it at 12V most of the time, and then whenever I want switch to 24V at the flick of a switch. I drew 2 rough Diagrams below to give you an idea. The 1st one is of the 2 Set-ups. And the 2nd diagram is how id like to run it. Basically at 12V it just gets hooked up to the battery as normal. With the 24V Set up, I have 2 additional batteries mounted in the rear of the truck, and a Charger Unit made by street charger, which will Charge a 24V system with a 12Volt input.  The Maximum load on the compressor is 200Amps@12VDC, but normally runs between 120 & 160 amps. The compressor also fills fast enough that it never really has to run for more then 2 minutes.  As for the 12V-24V Charger, Street Charger  has current limiting which will automatically convert to a trickle charger. Is there a special typeof switch i can purchase, or do I need any special relays, etc...

Oh, I forgot to put in. Here are thelinks for the compressor & street Charger if youd like more info on them. Thanks.

Compressor - www.oasisoffroad.com

12V - 24V Charger - www.streetcharger.com