My 78 G20 blew a head gasket last year. It was sucking coolant into one of the cylinders and white smoke was pouring out the tailpipe. I had built a 1995 350 roller motor and installed it 12 years ago. It looked too tight to do the head gaskets in the van so I pulled the motor. Didn’t want to disconnect all the A/C so I dropped it out the hole (the same way I did it 12 years ago). Tight fit but easily done. Used stainless steel head gaskets this time and also replaced all the engine gaskets along with new hoses/belts. The piston that is bright is the cylinder that was sucking coolant. Runs like new again. I had purchased this van new in 78 when I was 21. Has every option except rear A/C. Almost didn’t buy it because it cost so much, $7700. Couldn't be without my van this summer.
Yep, dropped it out the bottom. Took out the passenger seat, put the cherry picker through the door, picked it up a couple inches off the motor mounts, moved it forward slightly, tilted the engine back about 45 degrees and dropped it through the hole. That way I didn't have to take apart the front end and break the A/C apart. I just had it converted to 134a last August. The head gasket let go on Labor Day weekend coming home from a trip. Had been parked since then. Started on Easter Sunday and finished in 3 weeks. Took about 8 hrs to get it out. Twice that long to get it back in and everything hooked up. Could only work a couple hours in the evenings after work and on weekends. Had done this before 12 yrs ago so knew exactly what to do. Not a big deal (if you have the tools).