White smoke! Blown head gasket?

White smoke is water. After sitting dormant for so long, I would remove the heads and check for rust. Chances are even the head bolts may have loosened up a little after this much time off. I doubt they are damaged or the block is bad. Just a head gasket. Sadly the new style gaskets which will seal a lot of imperfections also are going to take away from compression. I had to have my cosmetic gaskets for my 273 made to make sure I did not loose anything and I’ve got the 4 bbl motor.
Good luck- keep her running. She deserves to be back on the road. Keep us posted too! Pics help.
Syleng1