OVERKILL!!!!!!!!!
Hey guys, this is OVERKILL!!!!!!
There is no need to overcomplicate this tiny problem with ICs or tranistors or anything. There is a very simple solution, which hotwaterwizard highlighted in my mind.
Goto an electronics store and ask for "latching relays" (you guys might have a different name for them) one for each button. I was actually given one to play with on Friday. It is the same size as a normal relay (mine is 14x7x10mm), but much better. You obviously connect the circuit to be switched onto one pair of contacts, and to the other (on mine) you momentarily feed it 12V, and it closes the other contacts. When you feed it 12V again, the contacts will be opened again. That is why it is called a latching relay, because with normal relays, they are only on when you supply them with power.
Well guys, I feel great, this is the first time I have been able to attempt to help someone else on this form, this is awesome.
I hope I am not too late though.