Cowl paint prep?

[PA Dodger]

I'm down to a few small areas of body prep before I start primer and body work. I'm at a loss on how to clean up the area under the louvers on my '69 Charger. I removed the large mouse nest and mouse carcass. Now I have 42+ years of crud/crust with a little factory red peeking out. I tried pressure washing already. Amost seems like sandblasting through the louvers is the only option.
Any thoughts? 

[Charger-Bodie]

Its a very tough spot. You are right about that. If you have many layers of paint peeling away under there you should blast it. If its mostly one layer of factory paint you may as well lett it fly.

[PA Dodger]

No such luck on the one coat of paint. I know that it was painted with laquer overtop of enamel at one point. I hear that's a big no-no. I don't want a big eyesore here. I thought maybe the restoration guys might have some trick up their sleeve.