It's refreshing to see someone doing their best to preserve these rare del sols. Good job! Be sure to keep those videos coming so we can see your progress. I currently own three running sols, one sol with a blown Z6 and a rusted out donor sol with a good Z6. Yep, you just can't have enough del sols (my wife thinks otherwise though).
With some d15/16 the cat can become blocked, I have a 92 integra and it had some smoke I replaced the valve cover gasket and it fixed it it may not be your problem exactly but I’m hoping it will help you
