Re-registering a <150cc bike

I looked and couldn’t find anything on this one. It seems to possible to re-register a <150cc bike if it hasn’t been reported as written off. Can anyone tell me what hoops you have to jump through to re-register such a bike? I would assume you need all the things you would to transfer registration plus an emissions test and safety inspection.

Cheers

kamiwaza

Plus the certificate of origin from the manufacturer. I would want to find out if the emissions test will be on the standards in force at the time of manufacture, or those in force now. If it’s the latter this could turn out to be impossible without resorting to bribery.