I got the underside (frame where it was notched etc.) and inside of the trunk painted today, I just used a semi-gloss black.... nothing fancy since it's a daily driver. The trunk will eventually be upholstered to match the interior anyway.... I also painted to underside of the roof, insides of the doors, and the floor.
I finally got around to finishing the welding on the trunk and the new drive shaft tunnel. I then primed the welds and put a seam sealer on. The seam sealer can be sanded and painted, which I will hopefully get done tomorrow.