A) Not sure how you keep posting tables in your replies... I tried cleaning up the old ones, but I'd rather you figure that out as you go along.
B) The heads are identical between the regular 3800 and the supercharged ones (just added injector holes for s/c). It's just the rotating assembly, mainly rods/pistons, that change the compression ratio.
C) For a "cheap" way to squeeze more from a supercharged build, many people run the non-supercharged 9.4:1 (L36, L26) bottom end with supercharged heads and intake. I ran this for years in my GTP and was able to optimize it, with time and tuning, to be competitive with friends spending thousands more on upgrades. Zoomer (owner of ZZP) actually convinced me to try it back in ~2006, and he's even been building up his personal GTP with an even higher compression setup for this season.
D) for a cam, I'd go for the X-P (ZZP) or S1x (Intense) as the largest ones that can be ran on stock heads, with modified valve spring retainers. Aside from springs/retainers/timing chain, you can leave the rest of the valvetrain stock, although you'll have to replace some bolts and gaskets while in there (and I'd freshen some things like the chain tensioner, valve seals, etc. that are exposed during the work). This is about a $1k or so venture, all said and done, since you'll need a few specialty tools, too (balancer puller with specific threaded bolts, valve spring remover).
Check out my 2020 Part 1 video, and any other cam swap videos on YouTube that give you an idea of what everything involves. Guys have documented this task a hundred times over, so you're not going in blind. Heck, even in '04-'05 I was able to learn during my first install with a step-by-step illustrated write-up before videos were more common. Roam the vendor websites, read up, and get to where you feel like you've already seen it done 10-15x before you even loosen a bolt in this specific engine. A. It's got to do something with my phone. If engine's 86-87 versus 3800's are similar I'm not sure I'd put a 66 or 67 on a mainly driven street terror, I did not like how laggy my 60-1turbo was and sold it. I do have to replace the cylinder heads right?