It is YOUR car, it does NOT belong to your insurer, should you wish to go through them and make a claim, they CANNOT settle the claim without your agreement, so simply state that it is to be settled on the basis that you retain "title"(ownership), they will be very unlikely to even try to charge you for the "salvage" due to the value of the car and their own accredited disposal costs, the gf's astra has never been charged for in 4-5 claims.
Any repair will only use parts that you are happy with, where no new parts exist you will be asked about whether pattern or s/h parts can be used.
Just take the money from the insurer, and repair yourself/garage etc.
Just be wary if it is AVIVA as they are at the forefront of dirty tricks at the moment, just like Nu were.
tabetha