Joe, this is part of a reply to your first question "How fast will I go with streamlining?"
There is a formal method that involves estimates of frontal area, drag coefficients, friction losses, the effects of altitude on drag and power, the racing surface, etc. It is good to know and most of us use it. There are frontal areas and drag coefficients listed on links to this website for many different vehicles. There are spreadsheets, too, to help with the calcs. A person can figure out potential top speed with careful work.
The author, John Bradley in his book "The Racing Motorcycle" (ISBN 0 9512929 2 7 for Volume 1 or ISBN 0 9512929 1 9 for both volumes) discusses this formal method. He also made a simple graph. It is a plot of rear wheel horsepower versus top speed from published data on modern road bikes. Road testers are hired guns that can tuck down very well, the "standard" bikes they ride are typically the pick of the litter, and tests are almost always done near sea level on a paved surface. The data resembles bikes at Maxton, Loring, etc. more than at B'ville.
The upper line on his graph represents road bikes with more than average resistance to motion. Resistance is friction and air drag. The lower line represents bikes with less than typical resistance to motion. A typical beginner guy or lass out will be at or near the upper line. A road legal street based bike well tuned with a good rider is somewhere between the lines. A well streamlined production road bike with a skilled rider is at or near the lower line. The goal is to be below the lower line. We can do this with our home built streamlining.
At B'ville the air is thinner and we naturally aspirated bikes lose power. I use a typical power loss factor for the salt flats. We race on a natural surface which creates more drag and we push against thinner air which produces less drag. My assumption is both cancel each other out for a street bike. I do not use factors for them with Bradley's graphs. The first post is an example of a little Honda.