It sounds like you're going for a rebuild, but if you change your mind and go for a wrecker motor, i recommend you find the most reputable wrecker you can. It will probably not only be the best, least-problematic experience, but even if it's more expensive (it might not be) it will probably be cheaper in the long run.
Many wreckers fudge kays and offer warranty's that are more of a problem than a solution.
In my search for a decent motor, i first arranged a motor with one particular wrecker, but when i arrived and checked the car that he took the motor out of, it had 40,000 more kays on it than he told me. He tried to manipulate me into taking it, but i walked.
The next one i gave a chance to, told me a good story, but what arrived on the truck was not what was promised. I checked into the engine number with the authorities. He tried to manipulate me but it got returned.
In between these were a number of wreckers that told good story's, but i didn't even give them a chance.
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wrecking 9/97 EL fairmont sedan burgundy 6cyl auto 270k modBAintake