Tom,

The AG fuel proofer, and the regular "hot fuel proof" AG dopes - as I recall- were referred to as CAB (?cellulose-acetate-butyrate?) material.

That was before the EPA became the good Lord's supervisor...

No one now alive recalls, or admits to recalling, what was in AG dope or fuelproofer.

The Fuel Proofer was an interim solution, when most all dope was nitrate. Nitrate dissolves in glow fuel, y'see.

Whatever AeroGloss "hot fuel proof" dopes were, there were enough issues with Randolph or SIG butyrates that compatibility became a post-grad study. As with SIG, EPA strictures have caused variations, even within the same brand over different batches. EPA may also have sealed the death warrant on AeroGloss aircraft dope products. LustreKote is different, entirely. And, not bad, if you shake the rattle-can the suggested 3 full minutes, and let it cure the suggested week or so.

This in reference to Lou's mention of LustreKote; I had some very revolting experiences with it as far as wanting to run, spit, apply too much material, etc. so solved the problem in the following manner.
This process solves the problem of getting spitting and way-too-much material, aka-weight!  I simply spray it into an airbrush jar while holding a paper towel over the opening of the jar to prevent loss of material and the smell as much as possible, thin it 25% with Dupont 3608S and then spray it on with the airbrush. 
This gives me a nice, workable solution and keeps the weight down as well as the spitting that seems to nearly always occur.
Will