Thanks for posting this!! Question: Is there any reason you did not fill in the small opening at the top?
Did this today on my truck. I am not going RGM rather I wanted to clean up the grill to look better after the butchering I did to it when cutting for the MX grill. Plan is to rattle can BSP the plastic to make for another low key mod to round out the truck. As a bonus after I cut the grill to install the MX upper I noticed when closing the hood the grill housing flexed more and the glass will strengthen it up.
Here are my thoughts:
1) Used fiberglass gel and it is messy! Not sure if resin would have been easier or not...prolly would.
2) Mix the bondo in small batches. Mine dried quick and then went on lumpy, which led to mad sanding to smooth it out. Also small batches equal thinner coats which means less sanding.
3) Buy, beg, borrow or steal a small powered sander. Started with a rough 3M sanding block and after a few mins I got smart and plugged in a Ryobi corner sander we bought a few years back. All of sudden the sun was shining, birds were chirping and I knew I had a chance of actually finishing it one day.