I'm having a problem getting my 95 Pontiac motor and transmission to mount together what do I need to do ?

Is it the original engine and transmission? If so check to make sure you have the dowel pins (should be 2 of them) lined up properly and get them close enough together to start at least 4 or 5 bolts. Then push them together slowly by tightening the bolts in one turn increments (criss-cross pattern) until it is together.