Why did someone splice into this IGN. 1 lead?

Those connectors on ign switch are aftermarket. Make sure its ALL wired properly. Someone's been in there doing something. Easier now than later.
A manual with proper schematics is a must if you dont have one. Dont repeat someone else's insanity.
Good luck.
Yep going through the whole thing with a fine toothed comb. and solder, mini files, disconnect tool, electrical tape and patience:thumbsup: