Hello forum! i'm new here and i'm having some serious problems as of late..

my car goes from working perfectly fine 3 weeks ago to suddenly just not charging batt light comes on and everything.. so i park it for a week.. well i go out buy an alternator from the local parts store you know usual story.. well thats where things get stupid and complicated and i have no i dea what... the PREVIOUS owner has apperently CUT the 4 wire plug going to the back of the alternator and spliced in a 3 wire plug so i had the white/blue, white/green & black/yellow wires hooked up to the plug the white red/ plug is just hanging there.. and ofcourse the white wire to the B post is connected well i notice that the splice on the wires is **** and one of the wires is barely hanging on by a strand so i pull it try to repair it based on what i see there but soon realize after installing and such realize its hopeless. so i try seeing if maybe its because the w/r wire is busted but no matter what i do this wire does nothing to help the situation... i feel lost and hopeless and have spent the last 3 days stumped on this situation..... i've been seriously debating just either selling the car or torching it or torching it and selling the chard remains because the previous owner micky moused so much on this car it deserves an honerable death like a viking funeral and not to go out like a bitch cuz the alternator wiring is fucked.. anyway.. basicly what has been done is this car has been converted from a 4 wire (not including the b post wire) to a 3 wire alternator system... what do i do because im lost and getting angry and need help