I have a 4X4 GMT 400 truck that I’d like to Cummins swap. Does the installation of your motor mounts require modifying my frame?

Yes. You must:

• Trim the raised area at the bottom of both motor mount saddles
• Use the included 3/8″ reinforcement plates (welded or bolted)
• Install countersunk bolts in the 3 uppermost differential case bolt holes
• Trim some differential case webbing