Im guessing the 'black grill' your on about is a dimma style? No chevrons and meshed? If it is, im a fan of these
You do know people only remove the rear wiper right? lol. Ive done this to mine and ive had no problems really..
As for the dials messing up it could just be wired up wrong or parts of the wiring are faulty?
Get some pics up mate