Without trying to hijack ths thread, can someone please point me to the topic which covers "metallurgy to reveal chassis numbers" referred to above (the search function does not respond). I have a similar problem with a disputed AC Cobra where the number may have been overstamped, and we need to see if we can reveal any evidence of the earlier number.
Assuming that your restoration is not yet complete and you go to VMR Pre War Prescott in a modern £10 (per car) to park in the Orchard on Saturday is far from expensive. Look at the web site for full details.
There should be a lot of action and interesting cars.
Even the £30 (per car) for entering a "proper" car including one climb of the hill (if you pre book) is good value.
Lookout for M type OG2438 or Alvis AFM781 and introduce yourself.