When oil pressure is lost gradually, the rod bearings are the first to go. You might get away with just replacing those. If you are less lucky, you might need to pull the crankshaft and turn the rod bearing journals down to the next size. If you're that far in, you'll be inspecting the main bearing journals and replacing the main bearings. The top end is probably ok. However, if you were looking for an excuse for a full rebuild, this is it.

When I was 16, I did the exact same thing to a 400 Chrysler V8. I ran it low enough long enough that the crank would have needed to be turned. I didn't like that car very much anyway, so my solution was to get a different car.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.