I've been getting my brain in a tangle, trying to work out what approximate F# that an F8 X F8 would give. Unfortunately it's not possible to tell because we don't know how many genes control the taiwan bee phenotype. What I do know is that by the time you reach F8, a lot of the CBS genes would have been bred out, so you most likely couldn't get a pure CBS genotype from the cross. My opinion? I would call it an F8 mischling X F8 mischling. Treat it as an F1 and it would be a good head start to breeding mischlings that you could use an F#.
As far as red bolts go, I'm in the same position as you. I've never had one (that I know of), but I have a white mischling that is quite pinkish/orangish in colour, so I've put it in with a ruby red to see what I get. Red bolt is possible from mischling x mischling, and red bolts are not the sharp red of a CRS. There has been some discussion on European forums as to whether a red bolt is a taiwan bee or just another colour variation of a snow white/golden. Someone crossed a red bolt back to a ruby red. The outcome? 100% red TB offspring! So proving that a red bolt is a taiwan bee! Your orange shrimp may well be red bolts. If they are not, they are beautiful shrimp anyway.