I suggest you contact Grob, They can send you a parts book for this thing which will come in handy. Blade guides too. I think they still make this saw.
Here are a few pics. I made the long drive slide from scratch. I've hardly ever used the power feed. No feel to it. But it does work. BTW it's air operated. At least mine is. There is an air input by the speed dial down on the bottom left side. If you ever have trouble shifting gears, try backing off on the tension. The transverse rod that one gear slides on is undersized and prone to flexing. Mine is touchy, and if you force things it gets stuck real bad. Rock the gearbox while shifting by opening the top cover and hand jogging the wheel. Hopefully yours will shift without trouble.
Dave
If you're running on a phase convertor, make sure you plug the 220 single phase to the two leads going to to the welder, or you'll fry the transformer first try. If you have it wired right, you won't need to turn on the phase convertor to use the welder.