The good news:
BERK HFC's are solidly connected to my headers.
The bad news:
Every muscle in my body hurts and I couldn't complete the job.
Only small items left: connect bracket to transmission and HFC's, connect HFC's to Y pipe, put one nut back on Y pipe (never even tried to get the rounded one off since I was able to remove the cats without removing the Y pipe).
One question: Do I need to remove the brace bolts from the old cats to connect the brace to the new cats? If so, how? If not, what do I use?