Thanks everyone for your help. I've only got receipts up to 1990 unfortunately. I know it got an oversill in 1991, but that's about all!
I have a bucket load of old Microfiche and to be frank, there is no direct connection between engine number and chassis number or commission number other than what Heritage may have, and even then, I don't think they can match an engine number to a chassis...
So, if your vehicle was produced after 1973, it will have a 10H791P engine as pretty much every engine during the 70's and early 80's prior to the A+ engine being introduced was a 791P suffix, be it an 850,998,1098 if it was in a mini.
Is it worth getting a hertitage certificate, are you not convinced they'll match the full engine number? I was thinking of getting one anyway before I resprayed in the distant future. Thanks again, this is all super helpful
