I agree with your adjustments, but it is impossible to believe Johnson will get 7.4%. The last not R, non D to hit that number was John Anderson.
I think J is looking at 3 tops.
Perot in 92 and 96 as well. I see Johnson’s #s coming down to 3-5% and Stein’s in the 2-3% range when all is said and down. Both candidates unfavorable ratings are just too negative IMO. I know a lot more people voting Johnson this time than last time as a protest vote in NC and see as many Johnson signs as Trump here (zero clinton signs or bumper stickers in Charlotte in my driving around at least.)