If that brand tells you NOT FOR USE ON FIBERGLASS...then don't test fate and be a dumbass by using it.
What ever the labels tell you....believe it!
Any good normal paint stripper will work fine for 6-9 bucks a quart.
Use good ole "Strip-ezze" ...."Kleanstrip" Homer Formbee.... all work great. I have stripped many a bird with whatever one I had on hand. Matter of fact just finished cleaning off the burned paint/mach rash from my 3 in. carbon project a few weeks ago. I've stripped PML phenolic also.
Use a metal paint roller tray. Good for up to 6 in rocket. Get a throw-away wood handled chip brush [.79-1.50 2in to 3in wide depending on project size.]
Do this outside in the shade...shade is extremely important. In sun and remover will dry to fast.
Pour some stripper into roller pan-paint well. Do not fill, just add more as you use it up. You must wipe out tray as you go, due to gooey paint falling off rocket. Do not waste stripper by having too much in pan getting dirty.
Stand rocket fins, at bottom on angled dry side of pan. Work on aprox. 2 ft. section at a time. I do all fins at once. As fast as possible brush stripper on area being worked on. Do at least 2-3 coats at a time.
Do 1.... wait just long enough it starts to act on paint, then do 1 -2 more. Let sit. DO NOT SCREW with it. Let stripper do the work. I use a plastic bondo spreader to remove gooey paint and wet stripper into another container.
Only takes 5-7 minutes in 70-90 temps to work. After I get fins and tube about 1 ft above fins done ,I flip rocket over and stand on other end. This way gunk from cleaning does not fall on fins.
Just stand payload and NC in tray and do same. Once you figure out how long to leave stripper on before scraping off, it gets very, very easy. Keep plenty of old newspapers on ground to wipe off your paint from spreader.
If you have some tough areas to get to, use the green 3m scrubber pads dipped in stripper to get in fillet area if simple rags don't work. Paint usually just starts to fall off when you keep paint nice and wet with stripper.
when bulk of paint removed, dip rag in stripper to wipe off residue. Finish cleaning with denatured Alcohol or lacquer thinner. Rinse with water when finished.
Needless to say wear nitrile gloves and glasses, you splash this in your eye and it burns like hell!
It doesn't harm tubes, gel coat or epoxy fillets. You only leave it on 10-15 minutes total to get job done.
Edit PS Aircraft paint is 2-part urethane such as Awl-Grip or Imron ...? heck I can't remember...... problem is once cured normal stripper won't dent it. It must cut through bonds similar to the epoxy your tube are made of. This type stripper is for Metal based materials that won't melt do to "HOT" strippers.
Way back in the day, we used to strip these type finishes off boat hulls by spraying M.E.K. type hot solvents on gallons at a a time. To do a 80-100 ft hull..... Hundreds of gallons pumped out of 55 gal drums...and pressure washed paint & stripper...ready for this. RIGHT DOWN THE FLOOR DRAINS!!!! That was before EPA got around to stopping all that . You should have seen how they used to strip huge jets.....basically the same