La Monte,
The way spotting in is normally done is to sand keeping the area relatively small, taper the clear coat edges if it holds. Then lightly scuff the clear coat with a red 3m pad out a ways into the blend area, then spraying just enough base coat color, blending outward into a light misting as you enlarge the area. Spot in several coats of clear coat fanning out from the center as minimally as seems appropriate. Each coat fans out a bit further then the last coat. The last clear coat is a blend coat to melt in the hazing of the new clear coat edge area. That is done by adding more of the solvent that the clear is mixed with. This last coat is quite minimal in thickness and a quick spray so it does not build up or run. The amount of solvent add is what works best for your materials and the paint supplier should be able to help with some insight. It would be nice if you had an old car panel to practice on.
This spotting in, may be much harder then just doing a panel like the top of the front cap, masking it off and just leaving a line in the clear for that segment of the coach where it meets the roof area color. I fear that you will do two spots and then another one or more will appear later. Paint work is not easy and good for you in tackling this. It does not have to be perfect is my bodywork motto, each time you do get better :-)
Later Ed