I have a sport with the tube style boards, do you feel that they should be removed?
Only if you like them.
4th gens have pretty decent rocker panel clearance considering how low they are. The rocker panels should be safe without the tubes. You might well touch the undercarriage but with care it should be fine.
what tires did you have?
32" BFG AT KO. One inch larger than stock, so 1/2 inch more ground clearance. Although the risk of flats is greater with P rated tires, it's still very small imo. It's a pretty well traveled road close to town so I wouldn't let tires stop me.
...was considering driving over the pass, to the spot where you are just above the steps then hiking it that what, I have read the road is two way till just above the steps, but not having been there I am not sure.
That's correct. There should be a sign, although when I was there it was lying on its side. Approaching from that side worked out well for me because even though I didn't intend to do the whole thing, I couldn't resist.
If you come in from the Telluride side, can you drive up far enough to get to the Bridalveil falls turnout?
Yes, that's where it becomes one-way I believe and there should be a sign. From there the tightest switchback is about .6 miles and the top of the steps is another 1/2 mile.
Also you mentioned that you felt that Engineer pass from the summit to 550 was hard. I have only driven Engineer from the Lake city side to the summit then over to Animas Forks and then over Cinnamon Pass. We drove the loop with Cinnamon first, then over to Animas Forks. The hardest part was from Animas Forks up to the top of Engineer Pass, as I remember some very tight turns, and some pretty steep parts of the road, nothing like Black Bear however.
The part I was referring to was the lower section which you didn't drive. I'm not sure how typical the trail was when I was there. The night before had a long, torrential rain and the trail was pretty washed out in spots. I'm going to guess its usually smoother judging by the trail ratings it gets in the books and elsewhere.