Iirc one of the letters appears just after that arrow crops up. My eyes are quite good still, but it can be a struggle to see these markings for sure. Especially if the bike isn’t raised up! When i’m tackling the job I find myself on hands and knees, torch in gob, spit dribbling down my chin, squinting like James finlayson and cursing as I glimpse the letter scooting past the window again.
If you’ve located the arrow, try going ever so slowly onward and hopefully you’ll spy the letter.