Power Supply Repair

I am working with a high school group that has a number of d40 fixtures.  Through the years,  the power supplies in the some of the fixtures have failed.  I am at about 80% success rate in repairing the power supplies, but a couple are just kicking my rear.  Anyone know if schematics for the power supplies are available anywhere?  Would be a great help in keeping these running and getting more use out of them.

Thus far,  three have failed with a blown ( literally ) control chip,  one with a blown power transistor, and one with a combination of the above.  Keeps me on my toes!