Most mk1/2 escorts have no chassi number anyway.

And most of the floor and bulckhead is probally made of sheet metal.

When you buy a mk1/2 escort you are paying for the panels that you can see.

If I was going to buy one i couldnt care less about what the car is on the log book, as its highly probably it isint that now (eg it has a new id)

All I would be look for is good paint and a solid shell.

There is know point in getting a new escort cosworth id (unless you have a stollen one) Because the escort cosworth shell is unique, It dosent matter what it says on the log book. If your car has an escort cosworth shell it is an escort cosworth imo.