Don't think those ever came with one. Look to the aftermarket as panther and CMC both make small units. As far as a tach that should be easy. Either find a timing light with the 2 strk function. Or buy a cheap tach off of ebay
Put up your starting procedure. Are you pumping the ball till hard? Raising the lever to get a high idle? Using the choke? Of you are going to use starting fluid at least use the stuff with lube in it.
It is more than a set of cables. The whole shifting and throttle set up are different for the tiller motor. That drive shaft is expensive because they break a lot.