So you have the car, the vin (chassis) tag and nothing else even though you say you went to the garage after being asked to remove the car???

You dont mention the model, why not contact the relevant owners club, Avo owners, mk1 escort owners, rs owners so on and so forth.

Failing that i would of thought once built you could take it for a vehicle check at a local office and get an age appropriate plate asigned??

Your story jumps about abit with differing info...hence the iffy statement...to be honest I'd of thought twice about posting if your not going to supply
tangible details.