Yes, I was talking about the back bumper step. You can use a trim and bumper paint or clear coat to renew your plastic. Works excellent! But, do it before the plastip if it needs it.
mdifilippo gave some good info. That first shot is an example of what your first coat should look like. After that you can go thicker. Also that wrap job is good. You can get over spray off, but its easier to cover a large section and just pull that plastic when done. The job is done at that point with no rubbing and scrubbing to do. If you get concerned about drips, just stop spraying when you feel that concern coming along. Its better to have to put an extra coat or two on vs. screwing it up and starting over! I did the dust coat on my grill and everything else flat. I'm getting ready to get rid of the dust coat, it's a real pain to clean.
Have had it on for 9 months and it is as clean as the day it was put on. Have a couple very small chips on the front bumper, I could just apply a small coat on them and you wouldn't notice unless inspecting closely. I have to redo the front bumper anyway, so will go heavier on it next time as well as the grill, 5-6 thick coats. In the shot below you will see some chrome bumper showing. If you don't have a gap to spray back under that, just take that upper portion of the bumper off. The entire chrome and edges should be painted, so that piece really should come off imo. That is a mistake I made. Pictures aren't great, was hoping to show the dust vs wet look. Storm was coming in just as I was shooting. The lighting gave the black a grey look. It doesn't look like that at all, it is dark black.
Also, just realized you were doing your rims, definitely get 6 cans. I haven't done rims before, but I have read they don't last long. Could just depend on the job they did. Lastly, the small wait time between each coat is boring, if you drink beer or smoke cigs, have them on hand Good luck, it will turn out fine!