70 engine harness to 72 dash harness

I have a 1970 340 engine harness but a 1972 fuse terminal and rallye dash harness. The only gauge that works is the ampmeter. I replaced the voltage limiter on the cluster but still nothing. Do i need to change any of the wire pins in the harness connectors. I am an idiot when it comes to electrical so dumb it down as much as possible. Thanks
Author: Old B5