You arrive T2, go through immigration, you will not reclaim your luggage (as this is checked through to PMI and customs will be there) and walk across the airport plaza to T1. There is a bus service airside from T2 to T1, however, walking is by far easier and quicker. In your shoes I would check-in online before you leave the US for your MUC-PMI flight. Two hours is plenty of time.