short history:
bought the 98 fzr600 a few weeks ago at least 3rd hand with no spark (was told a lady laid it down in a parking lot, and since then no spark). found the pickup coil was bent away from the flywheel - easy but aggravating fix.
now that it's running good i want to work on the plastics. i've read over 30 to 40 threads about fixing plastics, soldering abs, fiberglass work, epoxy, bondo - you name it. as i started looking closer - i think someone has already fixed this front fairing at least once before me - i just want a 2nd opinion.
front left side fairing ahead of the handlebars:

left side rear fairing:
also the rear fairing was rattle-can painted and looks... horrible. the best advise i've read yet was sand out the scratches and repaint - which i'll judge the depth of the scratches and decide accordingly. the front fairing is a different story, though.
the pics are low resolution - HQ one are available.
will i be better off just doing a "make shift" repair - i.e. repair what's broken - or sand out as much of, what i believe is the previous fix, and start over with a solid repair? i will also have to build up or add to - will i run into problems with the adhesion of new materials? what materials should i use?