Bob:
I didn't read all through this, but discerned that you want wide wheels and don't want to hit anything with the tire.
The only way you'll be able to tell for sure is to do a bunch of measurements from the wheel mounting flange on the hub, then in to the spring plates and out to the wheel well lip so you'll know what you have to work with, and then go out and measure the distance from the wheel mounting flange to each lip, then the lip to the outside of the sidewall of the tire. Then you'll have to do a drawing of everything, throw in the dimensions and see what wheel width and offset you'll need to make everything fit.
Just as an example (and I have written this up elsewhere on here in more detail): I have 16" 5-spoke Fuchs rims from a 911. They are all 7" wide. I'm running 205R50/16's on the front, and 225R50/16's on the rear.
I also have a 1-1/8" adapter/spacer at each wheel that goes from the 4-bolt, 130mm, VW hub to a 5-bolt, 130 mm, Porsche wheel, to get the wheels out into the wheel wells where they look "right". You could go as thick as 1-1/4" on the rear spacers and still fit OK with stock offset 911 wheels, but you might rub tire against the inside top of the rear fenders, especially if you have two heavier people on board. If that happens, then it might be time to set your ride height up a little.
Hope this helps..... gn