engine mount

Step daughters car has a few issues and I am starting with the water pump coolant system. She had it over heat and I couldn't locate the leak so just replacing items that could have caused the problem. Replaced upper and lower hoses. Replaced thermostat. Replaced radiator cap. Water pump...

I have 91 PA 3800 series I. I wish to replace the serpentine belt and notice that the engine is connected to the body/frame on rt side near battery. Should I disconnect this and then jack up the motor to allow the belt to slip on/new on... will I run into problems trying to allign the motor...