Advice needed on used crate engine

I forgot to add this earlier, but when I paid for it I told him I couldn't pick it up til next Saturday. He said no problem. I had a copy of all of the emails back and forth, so I could document everything that he told me about the engine over the last week. I asked him to write me a receipt on the back of them, showing that it was paid for and guaranteed. He said that his reputation is not worth ripping off a fellow Mopar guy and I agreed.

He wrote "Motor is promised to be a good working, kick *** motor, ready to rock & roll. Money back guarantee"

I think that about covers it!!