Al; I know you gave me your model number as well as put it here, but your motor should be a J/E25TEESB. That stands for 25hp Tiller, Electric start, ES 1990 model, B is the suffix. (Could be for lots of reasons). The model you give should be a rope start (R) & the rest is the same. Not sure why your model is electric start at the motor? If you look at a J25TEESB on the cylinder/crankcase page #91 is the switch #386056. One on eBay for $22 OBO, Free Shipping. That's pretty good, but I may have one.
Funny that two past service reps for OMC have now mentioned you can unhook it? That is not my first choice, but it will help you determine if that is the only problem. Like we talked about the switch is mounted on the ragged edge of engagement. Any little shim would make the switch/plunger engage more & therefore make the switch less touchy. It's a common problem with this system. Plastic parts wear. A new switch may not alleviate all your problems. FYI
Dan in TN