Wireing Problems...Need help bad!!

Ok... I didn't want to post on forums, but I have been haveing a problem that i can't figure out. Well, I have an 85 CJ7. I had the 4cyl in it and decided that I wanted more power. So I found a 258 out of another 85 CJ7 on ebay. All of the wireing harness came with it so im pretty sure everything is hooked up right. The problem im haveing is very weird and I've never heard of anything like it. With the key out of the ignition as soon as i uook up the battery cables I et power to the dash and the sarter turns over. Please help...im very confused at whats wrong...I have NO idea what could be causeing this. Also the Starter and starter cylinoid are are brand new so they cant be the problem...

sounds like you either crossed the ignition wires with the harness or the 85' and 86' had a different order for the ignition and starter etc wires cause it to fire. More or less you are hotwiring the jeep without even cutting any ignition wires to crank it. I would go back through the new and old harness and look at them and see if you made a mistake there.