Previa not Starting

Here's the deal, i bought a 1992 previa cheap b/c it had 'electrical problems'. After removing the 2 subs, 2 amps, 2 tv's, vcr, supernintendo, diversity tuner, and radar detector, i rewired the ignition and a few other plugs.

I charged the battery that was in it, and it was reading 10 volts at least (yes, my meter doesn't measure 12v well.). So trying to start it, the starter will start and turn the motor by a couple of revolutions, then the engine stops, the starter stops, and the solenoid provides a nice vibrant click. Further turns of the ignition may repeat the same once, then the solenoid just clicks.

Any ideas on what may be wrong? Is the motor seized? Or could it just be the starter? The starter IS turning the engine, but not by much, then it just fades to only the solenoid clicking.

I believe i still have an issue with the connections to the battery terminal. I can't tighten the positive very well, and it doesn't sit on the terminal well. Wiggling it will make the headlights come off/on. I"m thinking i need new wiring for the battery, but how will this impact needing the fuse box that's on the positive wire?

I would start changing the terminals with new ones, if possible cut a little piece of your cables so they will be a clean contact.