i used 18ga speaker wire, that way i only had to run 3 (2-1/2) wires.. my advice would be get inline connectors... i have strange angles in my wires because i used connectors like wire nuts that you crimp (dont know what theyre called but you use them for head units) anyway it makes it a little more difficult to get the wire in place.. all in all its a fairly easy process

id also reccomend installing quick disconnect connectors for your alarm LED while youre in there.. makes takin the dash off easier now and in the future