1. Wash the part with soap and water, then just water, use an air hose to find the ends of any cracks. Stop drill the ends of the cracks, I would use a 1/8" bradpoint bit.
2. Scuff the back side of the panel with scotch brite where you are going to do the repairs, do a larger area than the size of the reinforcement patches.
3. Pre cut your glass patches and test fit them. I would use a 6oz cloth and 1oz cloth. The 1oz cloth patches should be larger and be placed last, I would recommend you buy some pinking shears rather than borrowing your wife's. This is not to save you the fight, but rather an opportunity to win points AND buy more tools at the same time.
4. Use green or blue 3M masking tape on the visible side of the panel. This will prevent resin from getting through the crack and stop drilled holes and onto the outside/visible side.
5. Mix resin and apply to the inside surface in an area larger than the patch.
6. Lay the 6oz glass patch in place and stipple with brush to pull the resin through the cloth. Make sure that the glass is completely wetted. Then lay the 1.5 oz glass on top and use brush in the same way. Lay deeply cloth on top and stipple it as well. Make sure there is extra cloth sticking out past the edge of the part so you can grab it and peel it off after the resin is cured.
7. Let cure. Lightly sand with 120 to remove any glass spikes. Not needed if you use a peel ply cloth.
Tools and materials:
6 oz fiberglass cloth
1.5 oz fiberglass cloth
Peel ply cloth
1" paint brushes (trim to about 1" - 1 1/2" length for stiffer bristles for stippling)
Mixing cups and sticks
2" 3M masking tape
1/8" bradpoint drillbit
Pinking shears
Drill set to slow speed
Resin and hardener
West System, expensive
Generic stuff, cheap