45 electrical help
 

have a 45, believe a 1994 model. Overheat alarm keeps buzzing, telltale water is cool and plentiful, even so, replaced impeller. Next, tested thermostat, seems ok. Replaced overheat switch, no improvement. Pulled the engine to give it a flush and maybe more. Flushed out lots of gunk and am not keen to see what's behind waterjacket cover so am going to put it back in water and see what happens.
A presently unavailable friend was going to "improve" the wiring and cut the wire coming out of the fuse thingy, see photo. Where should it go?
Am proposing to attach the positive battery terminal to the bolt labelled "positive" on the starter motor (see pic) and the negative battery terminal to the bolt labelled "negative" on the whatever-that-thingy-is beside the starter. Is this correct?
Would appreciate help on overheat issue, getting things reconnected, identifying components (the thingies...).
Also, the engine serial number is a weird one: BAFE-1002669. BAFE?? Would like to confirm year.
Aaand, one more thing: purchased downloadable manual online, by eBlue-Dist. It's not very good because it covers ALL sizes for the years 1976 to 2005 and some of the info is incorrect. Any leads on a better manual that doesn't cost a fortune?