Spark plugs depend on type, it would help to know what Jeep you have and engine size. Most of the OEM plugs are copper so those would be changed every 30K miles. Plug wires dont really have an interval, they are usually replaced as needed or desired. Unless you want to replace them or have a problem I would say they should last 100-150k miles. Most people replace them for general maintenance reasons or doing a full tune-up (plugs, wires, and if applicable a cap & rotor)
Motor mount lifts are usually used to correct driveline angles after a susp lift was installed or just to try to help a driveline vibration. They can also be used to help position the cooling fan in the shroud after a body lift but thats not typical.