Herr Ramm

Hello, i have a GMC C5500Topkick 2004 Shuttlebus in Germany. I have to problem i need to fix. 1.)Someone know the wire diagram of the headlight switch? I will need what colour of wire is for the park lamps/marker lights. 2.) Someone has the wire diagram of the instrument cluster? In germany we have to install a tachograph, this is a unit which records the speed of the truck and wheater the truck is in park or in drive. Now we have to find the speed signal of the cluster and the signal from the transmission park/drive. Someone can help with this? Thank you and best regards David