Hey, when is this group gonna analyse Asa's jumping engine? Maybe it's like a Mexican jumping bean, has a bug in it.
I had a Ford like his with the same straight six. Put it in forward gears everything was normal. Put it in reverse and the whole engine twisted over to one side.
Broken motor mount on one side.
Front end collision, even seemingly minor = always check all the mounts. Doesn't take much to shear off or at least start a crack/weak spot in what is essentially a hunk of rubber.