Thankfully I have Ryan's book (
https://parabolicapress.com/products/porsche-turbo-3-0-book?variant=33250192076) and his expertise to piece together how the original factory paint process worked on these early Turbos.
On later US Turbos with higher ride height, or on cars with the low profile tire option, the factory would paint black on the inside of the fenders to reduce the visibility of wheel/fender gap. Porsche didn’t bother masking and just sprayed it on with overspray and drips common. Since my car has the low profile tire option, black it is!
Black paint was strategically used inside the car, the dash, the tunnel, seat mounts and other areas where carpet seams could expose primer/body color.
The inside of the smugglers box was always painted black.
Black paint was applied on the outside door edge to fool the eye into thinking any poorly fitting door trim was even.
The engine compartment was always painted body color, not black like they did on earlier cars.
The interior of the car did not get a full spray of body color, just primer. Porsche didn’t bother masking off the interior when the exterior was painted, leaving the inside with a lot of overspray of body color.
We stayed as true to the original process as we could.