O.K. You’ve got the race cans. A lot of these are legal if the removable baffle is in place. So first bit of advice; dont lose the bl00dy thing.
If, even with the baffle in, it’s still a bit marginal, the first thing a tester should do is to check that it’s stamped or plated with the EU mark for road use which, in this country, is BS AU (E) 193A
usually over 1990/T3
If that’s present, it is almost a certain pass unless your taking the p!ss.
Now, if you have been so enthusiastic with the polishing that the stamp has been worn away or the plate has come un glued and fallen off, you can buy new plates on ebay for not much.
Of course, it’s only legal to use these as replacements.
I wouldn’t suggest for a moment that you should spend money to try and circumvent the Vehicle (Construction and Use) Regulations, would I?