Detailing Wheelwells & Undercoating Removal

[Lost Pup]

I detailled the front plastic wheelwells and they look great. The steel rear wheelwells have a bad/partial undercoating job on them. The exposed steel seems to be painted the same color as the body and its looks good.
What would you do ?

Remove the undercoating and detail the well?
What product/method did you use to remove the undercoating ?

Or should I spray the rest of the wheelwell with undercoating and then leave it alone ?

[theveed]

why not repaint the wheel well with the body colour?

a local meguiar's detailer here in manila swears by keeping his cars looking brand new (untouched from the showroom)... so even if his wheel wells are undercoated, he still layers a coat of silver (his car is silver, obviously) over the undercoat to make it look new... it's the wells anyway, no need to perfectly match the shade...