UPDATE:
I got the other side cut last night:
Then got the new plugs cut and tacked in:
It took some time to form the plugs to the curves found on the Civic bumper, but worked out well in the end, the middle piece should be an interesting challenge since it's so much bigger.
I probably won't get to cutting the middle section and tacking that until this weekend, then hopefully find some time to finish the welding process (on both sides) sometime soon after that. The actual welding process takes the longest since I use a soldering iron to "stitch" the two pieces together and since my cuts weren't precise I have some gaps to fill, the I go over the welds on the visible side with a large flat tab on a soldering gun to smooth the "stitches" out. Then I will need to sand the welds (and the rest of the paint off) the bumper and use some glazing putty to fill in any imperfections that I find. Then I can finally paint the bumper.