Do not spray carb cleaner into the head. You will destroy your valve stem seals.

If you don't want to tear the motor down try doing alot of oil changes. Like at least 5 or six before you even take it out of the driveway. You can cap that coolant hose if you want and make sure you run your pcv lines correctly this time.

Personally I'd be pretty concerned about the bearings also. I'd pull the pan and check them out. You can replace main and rod bearings without pulling the motor but it is a pain in the ass to do the mains.