To remove the skylite is easy,but then you have the inside area to deal with. To remove the skylite,just pull up the skylite. Then measure from the center of the closest rafter to the center of the next closest rafter.They are normally 24 inches apart.Then get a measurement up & down large enough to cover the hole from the skylite & what ever rot that may have occured from the leak.Then just cut a sheet of plywood at the same size as what you cut out.(Make sure that you run the grain of the plywood left to right for the strengh of the wood so it doesn't bow.)Then nail a piece of base felt(Tar Paper) over the exsposed wood. Then replace with new shingles or what ever material the roof is. Be sure to follow the same pattern as the old material to avoid any leaks. Hope This Helps You
Sean
December 2007