Two days and I still think I didn't get a lot accomplished but it is what it is!
First I welded up the top exhaust inlet ring and welded it to the flange. Then I pop riveted it to the top half of the scroll. It certainly stiffened up the top a lot, don't think I need worry about that flexing anymore. I may regret leaving that foam seal on that exhaust inlet...time will tell.....
Then I tried using an orbital sander (60 grit) to remove the galvanization from the outside of the 8" duct but that was taking like forever, what you see is about 10 minutes worth!!!...... might have to pursue a different tactic....
I bought some 20 gauge (.040") sheet metal from IMS, a 1'x4' piece was like $6! Interesting they are practicing social distancing there. They would only let so many people in at one time and only if you were wearing a mask. They would also sell you a mask for $3 if you didn't have one. Saw one guy leave fairly upset.
Got the 20 gauge cut into a 48" x 6.625" strip and proceeded to put the sides on the scroll. Kinda slow with all the drilling and pop riveting but it came out OK. It was a bit tight wrapping the 20 gauge sheet around the scroll form, I don't think I could have done it with 16 gauge with no place to clamp.
You can see where I miss-drilled the one hole in the side2 and inside2 picture. I was still on the flange so I'm not worrying about it.
Here's a short video of it running with the sides in place. I didn't even have the all-thread tight at this point. It certainly blows more (subjectively) than before. It actually sucks my hand down in the video.
Tomorrow I'll start working on the exit/exhaust outlet with the cutoff in it.