Yes listen to JP. It's really not worth the hassle of a blown motor for the sake of a couple of hours.
Those R20's just go forever if you do the right things with 'em. I had one with 350K on it still going very well. On the 406 it's 80K or 8 years. But be cautious. I have a 406 in the shed with a blown motor courtesy of overstaying the timing belt change.
It is informative.
One piston is completely gone, with a con rod there where once a piston sat. The head is a write off with 4 busted off valves and big chunks taken out where bits of valve heads were pummeled between piston and head in the final stages.
The engine is a boat anchor.