ok, dont use the `paper clip method. thats worth a quick fix, but not for the long hual imo. instead, splice the two wires your going to jump into the main 24 pins cables, so that it turn on/off with the other one.
second, yes, you could use molex adapters, and further, if you wanted to get froggy, you could open up the psu and combine the rails to single or more 12v outs, and terminate them with a 6-8 pin as needed. just ensure that if you combine rails, do the same for the grounds. or, run a single wire or two from each rail (marked on the psu pcb) to the 6-8 pin.