I'd just call them up and say.....
“I’m aware the car is insured for black book value, and unless I’m mistaken, the aftermarket parts (wheels, tires, shifter…whatever) aren't going to increase the amount of my pay out if your adjuster determines the car is a total loss, since it wasn’t appraised pervious to the accident in order to determine it’s increased value based on the parts I installed. These are my receipts for the aftermarket items installed on the car (if you’ve got them) and unless you’re willing to give me a portion of their replacement value when determining it’s value, I want to remove them and replace them with the stock parts to help reimburse my loss”.
It should make no difference to them where you keep your aftermarket parts or not, if they aren’t calculating their value into the pay out price, so taking them off might be in your best interest. Besides, they're not there to appraise the vehicles worth (that’s predetermined by their little black book based on the vehicles year and mileage), they're there to determine the amount of damage sustained to the vehicle and whether it makes more sense for them to fix your car, or write it off based on its current value. Judging by those pictures, it’s a pretty safe bet that your car is going to be written off, but they can’t exactly make that call over the phone, so they’re sending someone down to look the car over in person.