guy,
appliance repair paint is NOT porcelain enamel repair
you can 'paint' appliances - including the SIDES of stoves - stove TOPS are porcelain enamelized - porcelain is not paint - [which is where you have pigments dissolved in a solvent] - porcelain is more like dipping something into molten glass - the porcelain frit is actually melted on at extremely high temperatures
remember - ALL paint will 'darken' with heat - couple links anyway:
http://www.forrestpaint.com/
[and click on the 1200 degree paint]
http://www.stovepaint.com/Tips/
this stuff still ISN'T porcelain enamel:
http://porc-a-fix.net/index.htm
these guys re-do the whole top - you ship it to them:
http://antiquegasstoves.com/
you might also think about having it 'chrome' plated - there used to be quite a few places doing that in chicago - which would be easy to clean up - but even chome plating will turn 'colors' with heat - [look at automobile headers]