I have found a loop hole and can avoid paying car tax altogether, simply register your car as a disabled vehicle as all disabled products are VAT exempt.
Just follow these easy steps:
A) buy a large motocycle, a 950 Triumph Daytona is fine.
B) find a nice stretch of road with a large Beech tree close by.
C) bring A and B together.
On second thoughts F***it, pay the Tax.