I saw a YouTube video of a guy that refurbishes dashboards, can't remember where he is located. Looked like an intense process using fiberglass. Got a new one from LMC in my color, fit like a glove, looks great!
On my 85, the nozzle attaches to the wiper arms via a clip-on feature on the nozzle itself. The hose comes out from the cowl, runs up the wiper arm and is held in place by a plastic "hose holder". Find it all at LMC.
Recently replaced my Cruise Control stalk and can say for sure that wire goes to the cruise control/turn signal stalk. Make sure you put it in the column before you install the column, otherwise, good luck installing it with the column installed. I tried for hours to get that wire bundle back...
Might want to check out Dapper Lighting LED's. I have them on my 85 C-10. No relays, no extra wiring issues, works with existing wiring. (833)-327-7371.