75-115 works good on a podded headered DOHC and 120 is too big for a stock muffler. The guy was flopping around like a dead fish trying to rejet for the pods. Maybe 72-102 for stock mufflers, just a guess but should be close. You may well be happy at the OEM jets and many are. When they rejet up for CVs (a no-no anyway) and they don't get a good result then they jet up more being completely lost on how the CV's work.
Carb bowl #2 just has to drop straight down to clear the pump shaft. The shaft simply goes into the guiding hole and bowl goes straight up when reinstalling it.
Yank the plugs, with the jets fallen out likely the plugs are wet fouled and you will not start like that. The plugs have to be dry. I use acetone myself, or let them sit in alcohol a minute then dry. Whirl starter over a bit with plugs out to dry the cylinders out a bit. Better result to let bike sit a day to air them out.
Helicoil is the fix for the stripped VC bolt. People just can't grasp the concept of a hit solid and stop bolt like used there, they keep thinking they have to torque it and the ones with VC gasket leak that think you overtighten the bolt to stop a leak? Well, they are forced to buy whopping numbers of broken parts over. I see people breaking that type bolt all day long on cars, they are much easier to work with but just trying telling people that. No, they only accept things being harder and not finding it so make it so.