I'm with Hank on the step plate placement..........IF you insist on having it. One way to get an "unbiased" placement is to have a couple or so people pretend they're getting in the car without your telling them why you want them to do that. Watch where they step without thinking about it.

On the welt. Personally I use it and paint the welt with the same paint the rest of the car is done in, almost disappears. The "problem" with using a welt with out the bead is it spaces the fender away from the body leaving an exaggerated shadow line that doesn't usually look much better than the welt in black (particularly against a bright color like yours). One other alternative if the fenders fit the body really well would be thin mylar washers at each bolt, they wouldn't give as much standoff but still offer rub protection with minimal shadow line.