I used my Dremel to grind/shave/sand down the edges of the fiberglass leaving me with my final form. I wanted to overlap the panel area completed which is slightly recessed.
Now after you've taken your two baffles, you glue them together and sand down the outside edges until they are somewhat smooth. I actually rounded my edges (with sander not a router) to help with my final form.
Notice I left 1/2" or so in front of the baffle to clear that plastic ledge.
Then take your baffle, glue and dowel rods. You have to do this in the car as to make sure you clear everything. Use the dowel rods to secure the baffle to the fiberglass structure using glue.
Once the glue is dried it's time to have fun! Carefully remove it from the car. It's time to fleece! Get your spray adhesive, fleece and gloves.
I sprayed the entire baffle, edges, and back side of the fiberglass part. Wrap TIGHTLY the fleece around the baffle and wrapping around the edges of the fiberglass box. You want it tight, no wrinkles, hurry the adhesive dries quickly. Don't cover too much of the sides of the fiberglass, just the lip. Because this part goes inside, you cannot add width or thickness to it. You have to sand down all excess thickness later.
Now get your fiberglass resign, mix it up some and put on a nice layer onto the fleece. Then put 2 to 3 layers of the matt and resin mixture onto of the dried fleece.
Once those layers are done and dried it's time to get your final form. I used my Dremel to sand down the sides, smooth down some of the rough areas. I also cut away the excess fleece that wrapped around the enclosure. So, keep sanding, and sanding and sanding.
Once you've sanded fairly smooth, spray some sandable primer onto it so you can see where you stand. You'll want a new car smoothness, so, sand, prime, sand, prime, etc.
Once you've reached a certain smoothness you may still have gaps, gullies, and other large valleys to fill. Bondo time. Follow instructions, use the plastic spreaders and quickly put on a layer in the areas of need.
Sand some more. Bondo some more, sand some more, etc. Or skip[ this Bondo part and go to the next step.
Here's the fun part as I found out. I'd say do this part right after you get your 2-3 layers of fiberglass sanded and primed and sanded as smooth as you can and skip the above Bondo step if you can or want. You'll no doubt have a few imperfections, and this will fix it all. Mix in the lightweight filler, 5:1 with the fiberglass resin using both recommended hardener amounts. You'll have a butter smooth liquid, get your brush and paint it on quickly and make sure to get a nice over all consistent finish. This step could actually replace the whole Bondo step but I didn't know right away and did it so I took the pics to document anyways. You can see how much smoother it is using the 5:1 mixture.
Onto to the final phase �