My opinion.... put the standard side skirts back on and the standard head lights back in. Get the number plate off and put backup for £4250 and take £4000 for her and sell the other parts on. I myself am not keen on the head lights or the side skirts and if others see it like this, could be the reason why it has not sold. I know a genuine buyer could see through this but the extra work to do to get it back to standard might be putting them off.

Good luck with the sale