I'M REPLACING MY FAUCET WITH A NEW ONE THAT HAS A SIDE SPRAY.THE HOLE WHERE I WANT TO PUT THE SPRAYER HAS A "AIR GAP" UNIT THERE. WHAT CAN I DO TO REPLACE THE "AIR GAP" UNIT SO THE DISHWASHER AND GARAGE DISPOSAL WILL NOT HAVE A DRAINAGE PROBLEM.
You can drill or punch a new hole for the sprayer on the opposite side of the faucet. This can be done in stainless steel or porcelain sinks using a carbide hole saw. As an alternate, buy a faucet that has the sprayer built into the gooseneck - no holes to drill.