Look up some YouTube videos on this. There's a guy that has a way of freeing them up shocking them. You might get lucky. If so, then I'd run 5 qts of oil and 1 qt of ATF for 500 miles or so and wash everything. See how it all looks and go from there.
You also might be better off finding a junk yard motor with way less miles to freshen up and install. Maybe find kne from a 2009 and then just tune out the AFM on yours.
You also might be better off finding a junk yard motor with way less miles to freshen up and install. Maybe find kne from a 2009 and then just tune out the AFM on yours.