LED S14 hvac

[i4jdm]

hey guys im doing the led conversion to my hvac and im in the middle of it right now.....i burned one circuit i think cuz i didnt put any plastic crap over the resistor and now i got another circuit board i wanted to know what like tape and such i can use to cover up the resistor so it doesnt cause any shorts......and when soldering do i have to be really carefull on not getting to heavy with the silver solder....NEED HELP SO THANKS IN ADVANCED