head gasket or cracks?

so I have been chasing all sorts of problems with my engine ($500 73 duster so I expected to)
it is running much better but I have discovered water is coming out the exhaust.
my coolant has no oil and i cant see bubbles.
my oil has no coolant
my exhaust spits steam and a little but of liquid water every time the engine misses.
the longer i idle the worse it gets and revving it up cleans things out for a few seconds.

I am getting ready to try the head gasket but can anyone shed some light on what they think is going on?