93 gauge cluster

Hi My gauge cluster is a strip model with idiot lights and no tach , I want to install a full insturment cluster off the same year xj I bought the cluster and pluged it in , the tach works fine , I changed the sending units fot the oil and water ,they work too my concern is the volt meter , has anyone done this and did you have any problems with the charging system Thanks

Have you used a DVOM and tested the actual voltage while engine is running? Adjusted/repalced your serp. belt? New cluster should not affect. Did you clean the connections really good before re installing?