You said that you can go for two months without the pay. Is the Owner and PM in the same position ?
If yes then you can talk to them about the sweat equity. It will give dignity to both the parties. In any case you fail. It will not give harsh feeling to anyone.
Some Doubts
* What is the default position of body tag? Static or relative ?
* In absolute position "the position context can be changed by giving the parent container a non-static position"
So the parent should be immediate parent or any parent will work ?