This may not be realistic,but I’ll ask anyway. I’m looking for a tdi, there is a stunning one in Scotland, but slightly higher mileage than ideal, SO, this is a car I will drive every day for the next 5 years, then will be reluctantly given to my son as his first car. I will accumulate the mileage, had anyone dropped a low mileage engine in to replace the higher mileage, or a. Are they impossible to find, b. Not that easy to do and expensive c.ever been done before? Thanks so much.