How to fix small rust spots before they turn into big rust HOLES:

-sand rust w/ coarse sandpaper or grinder till metal is shiny
-clean area
-treat w/ rust inhibitive of your choice (extend, naval jelly, metal etcher,
other brands)
-clean with paint thinner/mineral spirits/prep solvent - remove all dirt and
rust residue
-dry area
-fill w fiberglass or epoxy metal, or braze up holes (or if SMALL pinholes,
bondo is ok (paint ~usually~ wont stick to silicone, tho i have done it with
ok results) larger holes require new metal to be mig welded in.
-let dry
-sand till smooth
-clean area
-mask off area
-prime
-top coat paint and clearcoat (if applicable)

chris