Wanted Caterpillar 4600G engine or parts

I know this is a long shot and im not the only one looking but I'm looking for a complete 4600G 6cyl gas engine in any condition or a set of heads at the very least. They were used in 6M 12 graders, 3R natural gas electric sets and of course the R6 which im trying to locate the parts to build as non exist. Yes these are as common as unicorns 

Thanks Josh

Josh, I wonder if there's a relatively common cylinder head that might have the dimensions to be adapted - unlikely but maybe worth a couple of hours of research? The only other approach I can think of is to adapt a D4600 head and maybe shave the piston tops

Hey Josh. My father just asked me to do some research on selling a D4600 that was installed on our hog farm in southeast iowa. i stumbled across this community and this thread. thought I would reach out and see if you are still looking