The negative wires can be hooked to the frame and will offer less of a chance of building resistance later down the road...
For the positive side wires best option would be to get all of those wires off the battery post, set a relay and in-line fuses rated for each device on the wire going to the device, and have just one feeder wire running from the battery to the relay.. also fuse it for the proper size of the wire (ie: #12 wire would be 20 amps max.) Relays can be found at just about any auto parts store and are fair cheap and you can get them rated for 30 amps (or whatever size you need), and most have spade terminals that crimp on's can be used on the wire ends. Having wires hooked directly to the battery can be dangerous as the battery amps up in the hundreds, and in a ground short will melt down some really large wire sizes... any wire coming off the battery directly should have a fuse as close to the battery as possible.
Last edited by MusicmanM58; 02-11-2010 at 07:09 PM.