Nissan Repair: Reverse Lights dont work., nissan hardbody, electrical wiring

Question
Recently I took a 97 Nissan Hardbody Manual transmission and engine and put it into a 1995 Nissan Hardbody Shell. The 95 truck was an Automatic.
After the swap, the truck wouldnt start so we installed a push button and re-routed some wires.
Now the reverse lights dont work.
Would you be able to tell me if installing that push to start button couldve been the problem to not having reverse lights ?
And if it probably is, is there a better way to get around the starting issue without affecting anything?

Answer
The reverse lights are activated by a switch that is mounted on the transmission body. Since the electrical wiring from one vehicle to the other is different, it needs to be modified. First, you will need to find out if the switch is working properly. A 12V power needs to be supplied to one of it's wires. When the gears are on the reverse position, the switch "closes", thus allowing the voltage to travel back to the lights. The lights are grounded by the body-chassis-engine grounds so make sure that all battery grounds are connected, clean and tight. :)