Gauge Cluster

[hanly2]

I have a 70c10 with a 3 hole cluster, I guess its called. It also has one of those cheap sunpro 3 gauge things hanging under the dash. I would like to switch to a cluster with all the stuff in the same spot. I have a spare one that has the 4 holes on the bottom, but I am not sure if it would just plug in to my truck or not? I also would need to change the battery gauge and stuff I think. Has anyone ever modded their cluster to update it like this. Maybe I can put the sunpro gauges in the 4 hole one or just cut the one I have? I also want to add a tach somewhere in the cluster. I don't want to buy one of those 400 plus ones. Any ideas or pictures would help a lot. Thanks.