imo....take the emblems off......or order brand spanking new ones. don't have to be the 06+ style, but it's definately easier to work with with them not being on the truck. Plus new emblems are only like $15 each, so it's cheap and easier to work with new stuff.
I used Duplicolor Adhesion Promoter...that's basically a clear primer. no sanding needed. I love this stuff, have yet to have a chip in anything that i used the adhesion promoter on. Then color. Then clear, a nice good layer of high gloss clear.
I'd also remove all the black, so you've got a uniform color to go ontop of. i've been working on a how-to involving both ranger emblem styles. Here's a vid on removing the black 'paint' from the emblems...same theory on your style emblems.....(said some things wrong...want to redo sometime)
And a link to my modded emblems...basically a complete how-to...