Since finding a fender in that color probably won't be easy around here (I never see silver E34's in the Seattle area) I'd just swap some basketweaves on there and sell the style 5's then sell the car as is.

Filler plate probably could get you a couple of $ if it's easy to take off & leave the car intact (haven't installed or removed one of those yet so I don't know). If you've still got the factory tails to swap out for the Hella's that'd probably be worth your time. Otherwise I think it'd be best just to sell the 5's & sell the car as is. Honestly see the 5's as being worth the most amount of $ out of all of that. The suspension stuff isn't worth anything used. Especially if it's that Meyle HD M5 kit that's on eBay constantly for next to nothing.

Do enjoy the 540/6 when you get one. Having had extensive experience with both a '93 M5 and my current M-Sport I do believe the 540/6 or M-Sport's to be the best E34's for everyday use. Much, much better in city use than an M5 is.