Rain gutters and body seam sealers

I normally apply the OEM bead in the same window that the TDS of the epoxy I use advises to put filler on. In my case, The TDS says to allow the Epoxy to dry 24 hrs before applying filler...So that's my window. Also, You can use a tight rubber glove with your finger dipped in lacquer thinner to smooth the sealant out. Just don't wait too long.

Also, if you are buying the gun, you might as well use the 2 part everywhere instead of the brush on. Especially under the hood, A pillars to rocker seam etc. Get a couple of extra mixing tubes (nozzels) as well. Then you won't have to rush the job.