Bike-engined - should I just scrap the donor?

[hillbillyracer]

Now there's something I dont like in that emissions data table, engines of an unknown age are subject to a post 92 test! What if you got a c#%* of an MOT/SVA tester & as you could'nt prove the age of your motor it ended up in the post 92 catergory? You could have a Kent or a Pinto which pretty much have to be pre 92 but have to get it up to the later emissions standard.