Re: My new 1996 E350 World Trans Shorty
I think that batteries rated in Cold Cranking Amps are starting batteries, designed to give a quick high-current shot to get the alternator turning. More plates, but thinner plates, less acid.
I think that batteries designed for deep cycle use are rated in Ampere Hours, and have fewer, thicker plates with more acid.
Since you do not have a big battery bank, a couple of tips:
If you have not yet bought a microwave, look for a 'cheap' one with a rotating dial for the cook time. Ones with keypads and digital displays use a little current all the time to keep the computer actively looking for key presses. Alternately, unplug a keypad microwave when not in use, or put a switch on the outlet to kill the power when you are not cooking.
The same goes for a TV that you can 'turn on' with a remote control. If it can accept instructions from the remote, part of it is already 'on.'