Flowmaster cat back rotted and a simple tranny question

Hola all long time no c as usual. Lifes been really busy. So I finally am back to work on my stangs, I am working on my newest(purchased in 05) 89 mustang vert. It has a long list of mods one of them being a flowmaster cat back. The thing is really loud and has been since I got it due to the mufflers not actually being used. the cat back is rotted right at the h-pipe, I believe its a bassani h with cats. The collectors are still bolted up, but the pipes broke off right at the flange. It is a two bolt, and one of the pipes has a crack in it about 17 inches long. How should I go about fixing this? I am just gonna go to az and see what they have, but thought maybe you could give me some pointers.

Also, I have not driven any of my stangs for at least 2 years. I pulled this one into the garage, and when at the bottom of my driveway the tranny was not in gear, I had to rev it to get it to catch and then I shot up my driveway and it lost drive again, only for me to rev it and be able to drive in. I know it has a tranny leak, and after 2 years of dripping I am guessing it lost between 1 and 2 qts(judging by the amount in my catch pan). Think I did any damage to the aod? and what kind of tranny fluid do I need to put into the aod. It is stock with a lentech valve body. I really dont want to rebuild the aod... but I guess I will if I have too. Thanks for any help

So I guess imma just go to midas and have them do their touch.

How about the tranny? Is there anything special I should put in it, and do you think it got damaged by running low on fluid?

Thanks alot, all I ever hear about is how weak the aod is and it makes me nervous that now I have one

Cool. Do you mean don't go wot ever when in overdrive, or is it ok to go wot as long as it can still downshift? Getting my stangs running again is awesome. thanks for the help