This is probably a dumb question but I have to ask

[ZionBound]

So I just started refinishing a neck for one of my first basses I sanded everything down and put on about 3 coats of paint because I wanted it all black, fretboard included. My question is this: in reference to inlays is there any wiggle room in regards to their being flush with the fretboard. I have some very thin metal crosses that I would like to use as inlays but don't want to have to cut into the fretboard in the shape of the cross. Can I just lay the metal in the appropriate spot and finish the board with epoxy like I had planned in the first place. Or would this affect the playability even if the surface of the metal does not breach the height of the actual fret? Any help would be much appreciated. And being that this is a project guitar and I have other guitars to gig with please feel free in being completely honest with the best advice, even if that means I have to scrap the little metal crosses that I bought.