Yes, I know I am quite late in the game, but I had the same issue. Aircraft stripper for fiberglass nor did Easy Off get the job done. I had Xtreme Powder coating in Grand Prairie, TX. Plastic media blast them. It was done at low pressure and did absolutely noting to the grain or integrity of the panels. I am completely happy with them. I do recommend that you use an adhesion agent. I used Bulldog. I shot them, and followed up with three light coats of color, then I used vintage clear over them. They reason I love vintage clear is because the sheen can be controlled just by adding more or less hardener.
The Product will yield flat, eggshell or semi gloss. I recommended the 10% addition of urethane reducer, as it flows better and allows very thin coats so you don't fill in the texture. I know the crowd here is going to say that isn't how Ford did it, but it yields an equal result and as Bob says: No one is going to know but you!
I used two stage in the engine compartment, and it looks factory, but so much more durable than factory single stage.
This is especially with a big block shoe horned in.
I hope this is helpful...