lots 'n lots of them dont have the right engine and unless you have the origional documents who would even know. We know that the number range can be determined and you can spend your life hunting blocks and get close.
Back in the eighties I blew the 308 in the SLR5000 racing my mates XC on the way to Batherst. The go then for penniless people was to roll the car into an engine reconditioner and pick it up in the arvo. Thousand skins and you were back on the road, all sweet.
I guess unless it was special like an L34 moter any reco'ed L31 was the same to most people then. As these motors hardly last 40 years if driven and most of these cars were not shedded with an eye to keeping them... I would imagine most would of been swapped at some stage whatever the sellers tells you.
Mauser
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