Got a 1982 K5 6.2 diesel. Got it from a friend who intended to build it up, but died, so his widow sold it to me. Anyway, dragged it home as it had been sitting for 3 years, slapped 2 batteries in it to fire it up (after checking fluids). The engine turns over, but won't start. Noticed the Engine water level, so went to put water in radiator, and it all gushed out the back of the engine. I assume the freeze plugs need to be replaced. My question, how much trouble is it? Will I have to yank the motor out to fix them? I've never done freeze plugs before. Is it woth it? I've already dumped $175 into it with tires, etc. The interior will all have to be re-done, but no rust.