69 Tach wiring

I've got a 69 mach 1 that came without Tach. Now I've purchased an original instrument cluster with tach and I've discovered that the printed circuit wiring differs between the clusters. Does anyone knows if I can rearrange the wiring in the multicontact that connects to the cluster or do I need to cut the wires behind the multicontact and reconnect them in the correct order? Is there anything else that has to change? The cluster with Tach has warning lights instead of gauges for some of the functions (such as oil preassure) but I assume I only need to change the senders in those cases. I appreciate any advices in this matter.

Thanks,
Patric

Max Power!

You rule

Thanks for the information. I was seconds away from putting back the standard cluster but you saved the day. I'll be splicing and cutting this weekend! I hope the cluster works....

Thanks again!

Patric