Finished adding all the nutplates and then added a smear of ProSeal to the upper portion of the lower flange and fit it to the firewall and fuselage side skin. Of course, it fit perfectly. I added the small cowling side hinges and riveted them to the front fuselage. Then I prepped up the two stiffening angles for each side of the forward fuselage skins. Mixed up a big batch of ProSeal (sealant) and then sealed the firewall, dispensing the sealant with a syringe. It made a pretty good mess but I cleaned it and smoothed things out as best I could. Then riveted on the stiffeners. I'll have to reprime the inside of the skins. No big deal