I know most first time builder just want to get the parts on the bike and ride ASAP, but if you make the time to look at the bike and kit parts an $8 can of High Temp Motor Paint can make a big difference in how the bike looks when it's done.
Unless its a white or silver bike I tend to always paint all the kit brackets and mounts to match the bike, and for dark colored bikes I like to paint the 3 side covers and head black, but occasionally a bike comes along that could use a touch of another matching mount and motor color.
I keep silver and black 500F motor paint around all the time but on a couple of recent builds blue seemed more appropriate and sure enough the wholesale auto parts place around the corner carries all kinds of High Temp (500F) colors!
This is how these last two blue accent builds turned out.
To me there is a subtle but discernible difference between a bike that looks like it just had a kit added, and one that looks like it is actually part of the bike and just some paint can do that.
Post some pics of your builds where you managed to make the motor and kit parts look like they actually belonged there, I'd love to see them ;-}
A couple of notes:
I have the luxury of usually having the bike in hand to motorize, have a week before its kit arrives but every mounting part in it on hand so I can start with some paint work.
When painting the head I just put an old spark in that hole, some tissue in the 4 bolt holes, and with a little masking tape cover a head gasket and lay it over the cupped combustion chamber and mount metal. You don't want paint in any of those places.
I also found just a metal coat hanger with a series of 'wave ripples' in the bottom part you can hang most every mounting piece and even the tensioner on it and spray paint it with ease.
Again, just tips if you want to try it and please show your efforts.