There's no specific block for manual or automatic, so you could totally use that XR with a manual. I believe all cranks are machined to receive a pilot bearing, but I could be wrong.
Engine codes:
https://pontiacpower.net/numbers/engine-codes/
WN looks like a 250hp 350 with a manual trans in '71. The numbers above the two letter engine code are just a production number. I don't believe they match anything else. The partial vin is stamped down on the lower front size of the block. That's supposed to match the vin plate on your dash.
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Ken
'68 GTO - 464 - Ram Air II heads - 236/242 roller - 9.5” TSP converter - Moser 3.55 Truetrac (
build thread |
walk around)
'74 Ventura 350
'69 AMC Javelin SST