Trouble with a cummins 4bt

Got a 1991 dresser td8g dozer with a cummins 4bt. Was working it the other day nothing hard just clearing a field. The 1st problem I noticed was a blown exhaust manifold gasket, pretty bad leak though. So I started toward the garage with it about 700 yards away. Started running rough, missing maybe. So I idled down & it completely died tired to crank it, it won't turn over. Looked engine over noticed the access panel for the push rods is knocked out away from the engine block, so I'm assuming bent push rods. Checked the oil no metal but way over full & is low on antifreeze. So I believe coolant is in the oil. I'm by far not a diesel mechanic, I can do the basics to keep them running. But I'm in trouble on this one. Engine was holding good oil pressure & wasn't running hot. Any help is appreciated, it's a great dozer way to good just to let it sit has been in my family since bought new. Thanks Brandon

Trouble with a cummins 4bt