The drawing in the article isn’t a Flyer/Rep type gearbox. It looks like a fairly early Three-Speed Super box. (The article is dated 1926, so clearly pre-Flyer/Rep/Sprint Special)
The conversion to foot-change from hand-change offered by the factory was a VERY cynical affair as the adverts failed to mention that the gearbox shell needed some precision engineering to position the indent plate in exactly the right position. What happened next was a total can of worms, because you would have both gear-lever and rear brake pedal on the R/H side ! So you then had to try and find a left-hand brake pedal, BUT you probably had a left-hand exhaust system typical of hand-change Flyers and TT Reps and Sprint Specials, and a L/H brake pedal would foul the exhaust ! If you were able to buy a later type L/H brake pedal, you would also need the appropriate gearbox tray clamps, AND a crossover shaft, shorter rear brake rod, etc.. To do the foot-change conversion properly you would therefore need to buy the bare positive-stop mechanism with pedal, get the gearbox shell machined to take the indent plate, then buy a L/H brake pedal, gearbox tray clamps, crossover shaft, shorter brake rod, and a right-hand side exhaust system !!!
There could be yet more problems, because the spring-loading of the ball or plunger for the indent plate tends to try and pull the selector bolt out of the box, and you would need the later type of selector bolt, which has a big slotted head to prevent that happening. It just went on and on, and the poor mugs who fell for the adverts would end up spending a small fortune in order for it to be a success…
