^^^That looks awesome Buddha
Id stay away from green cause its not sexy and stick with yellow cause it is hot..
The easiest, cheapest way i reckon is you just rub it back a bit till you start seeing undercoat, fill scrathes and such with spray putty as you go, then spray yellow over the top again..this way you dont have to worry undercoating it again or about door jams, under bonnet etc
For best results you can hire a proper spray booth for a day as well, prepare it first then drive it to a spray booth ,mask it up and spray, then drive home and cut it and your done.Have seen a few people do this with some great results..One of which was a bright yellow panelvan and the guy had never painted before and it looked great