67/68/69 cuda dilemma

I also ordered a small borescope off evilbay that works off my phone. About $12 shipped, and lighted. Comes with a mirror attachment to see around corners. I am planning on pulling the cowl to fix any corrosion in there, however I want to survey how bad it is in there before I pull the upper cowl off because if its not repairable and I need a lower plenum I'd like to get one now. Its solid as far as poking it from underneath with a screwdriver, but I blew out a lot of junk and rust chips a few weeks back. Nice thing about the borescope is its lighted, and i can snap pix with it on my phone.