If the rings are still on the pistons and the bores aren't re honed, explain where taking them out and then putting back in their respective cylinders is gonna fail?
And a used oil pump from a new motor that has only about few hundred to a thousand miles on it 'like new' unless metal/sht went through is just fine to re use.
Im sticking the same oil pump back into my refreshed 410, because it's still in spec...and the same used pistons....and drive...and timing chain....
