I Messed Up!!!!!!I BLEW It Up!!!!It's Time To Fix It.

I built this car 10 years ago. The motor sat a long time before it ran, its about a 2009 6.1 HEMI Crate motor with a MOPAR AEM Computer. I got it going a couple years ago, put a thousand miles on it and then Destroyed 3rd and 4th gears in the transmission and then the
Motor. It is a Kiesler Conversion with a GM 4L60E Automatic. I doubt the motor is worth fixing? I figured Id put another crate motor in it and would hope it had a Different Computer{I could not find anybody that knew that computer} I think another 6.1, 6.2 or 6.4 would work???
Just need a little help figuring this one out. IDEAS???????? Thanks Ron
Oh Yea, that's the piston that came through the back of the motor

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