All finished and it looks like a million dollar class C. As reported, the hardest part is the prep work, using a small scrubbie but all the black streaks and anything else came off with a little elbow grease. I guess I overkilled, but used BKF, then TSP, then Dawn and of course everything was washed off and left no shine whatesoever. Putting on ZEP was a breeze as everyone mentioned. I used a small cloth to put it on all the rubber and around the windows first, using 4 coats as recommended and the results were amazing. I used an old 4 litre (gal) plastic ice cream bucket to put the wax in for applying it to the RV, even the graphics, which also were previously scrubbed with BKF, then using rubber gloves I squeezed out the microfibre cloth. I found that by wiping off my gloves on the cloth after wringing out, I had no drips at all. It took me longer than expected but it was well worth it. The shine is incredible and I also put it on the hood of the Class C.
Thanks for all the postings and one should take there time reading them before starting the process.