Alternator Wire In 9 Pin Plug

[unariciflocos 49 1 Cars]

I've rebuilt my entire loom for my Megajolt conversion, everything is running perfect, but there is one thing I think I got wrong. There is a wire in the 9 pin plug that is marked alternator, so I connected it to the + of the alternator. This seems to be wrong because I got a warning light when the key wasn't in the ignition. Should I connect the alternator wire to the switched live?

 

I'd also like to keep running the tachometric relay for the fuel pump, would this work if I connect the tacho out from the Megajolt to it?