Obviously as a 'grease monkey' you can not do the job of the 'spark' because you are unable to competently plan out a basic two way wiring plan without seeking advice. Can I ask how you propose to test and certify the install, notification of works etc.
I have no issue helping anyone where I can but matter of factly, your attitude is what stops people from affording you that help.
Although you could probably talk me through fitting my own brakes to my van, would I do it....no, I would take it to someone competent, with the right tools for the job and the proper knowledge, because brakes are something that, if not done correctly can kill later down the line, just as electricity can!!!
Rant over