Welding Frame Reinforcements

["Ronald A. Dowty" <rdowty@iso.net>]

I just got my frame back from the sandblaster (he did a horrible job but
that's a different subject). The bad news is I have a crack or two around
one of my differential mounts. I was already planning to add the
reinforcements to the frame. I have have two questions.

1) Do I need to do anything additional since I have the cracks (they are on
the part of the frame that has the donuts on eachside where the rear springs
go)?
2) What power of a MIG welder do I need?
3) What gauge steel is the frame and the reinforcements?

(OK three questions so sue me)