There are two sets of coils that have to be cleaned. The condenser is the hot coil and the evaporator is the cold coil. From the top, the evaporator will need to have a sheet metal plate removed for inspection. When you replace the cover, you will need to use the aluminum tape to seal the joints.
On a maintenance note, we have found that we need to clean the air filters about every 7 to 10 days of use. We do have two small dogs and a parrot.
When you tighten the bolts on the inside, just snug them up. If you over tighten, you will crush the gasket and probably make the leak worse. If the snugging of the bolts does not sop the leak, you will need a new gasket.
The gaskets are not expensive and are not hard to replace. Above all, do not use any caulk on the A/C gasket.
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Standard Schnauzer and one small Timneh African Gray Parrot