Christmas came early.
The mailman brought me a tach from ebay:
a pocket bike chain guard and two chain tensioners:
1/2" ID fuel hose for my oil dispenser:
Brunton fuel pump, which screws directly to my existing bottle:
1/2" brass fittings and valves arrived earlier this week.
Tach came with instructions, should be easy to install. Need to make a bracket.
Aluminum chainguard is thin. The Tanaka expansion pipe needs to be moved 1/4" outward to clear the guard. Since the pipe is MUCH thicker, I might just leave the pipe alone and trim the guard to clear the pipe. The supplied chain tensioners are smaller than the one I made from a skateboard wheel. To clear the chain guard, skateboard wheel or new tensioners will have to be relocated further from the drive sprocket.
I didn't realize that the 1/2" brass fittings would be so heavy! Maybe I'll keep the 1/2" hose and downsize to smaller fittings and valves.
The fuel pump pick up line is too short, since the bottle is laid down, not upright as in my cage. It should be no problem to lengthen the pickup inside the bottle.
I have 10 days' vacation soon, so I'll rebuild my wheelset, regrease my gear box and install everything else then.