Accidental Straight-Pipe and Unrelated Brake(?) Noise

Hey all,

A few weeks ago, I started my truck and realized it sounded like a big old V8 with race headers instead of a polite, respectable stock Japanese V6. When driving, it was LOUD. Climbed underneath the next day and realized my catalytic converter decided to take a vacation from the downpipe.

For my neighbors' sake, and my own long-term hearing ability, I'd like to put the hush on it. My question is, how do these parts go together? I tried looking at exploded view diagrams or parts finders, but they don't give me quite the information I'm looking for. Is it a slip fit, and I just need to loosen the flange bolts, slide it back together, and re tighten? Or did that rusty pipe shear clean off when I hit a bump? It looks too clean of a line and too dirty of a finish to be the latter. I'd like to know what I'm up against before I go ripping the thing apart.

Onto the unrelated noise: I had the brake lines replaced a while back after a blowout. Afterwards, from just above idle to about 2,500 rpm, I hear an airy, puttery sound from the drivers side, under the hood. It stays a relatively constant rate until it bleeds into a hiss, then kind of fades away under increasing throttle. I'd post a recording of it, but I need to fix my exhaust first My best guess is that it's some leak with the vacuum booster. Anyone with a little more between the ears have a suggestion?

1995 Tacoma SX, 3.4L V6, 5spd
Thanks!

 

the downpipe flange is (actually was) welded to the pipe. It needs to be rewelded

 

That's the answer I was actually hoping for! Gives me an excuse to take it into the welding lab at my community college and play with the expensive TIG machines.

 

looks like it probably wont take well to welding by the look of the flanges... might need to 2 new flanges welded on

 

Tig won't work too well on that at all my man, Tig likes clean pristine metal not that rusty corroded stuff you got going on there. Your best bet is to hit it with some mig either flux core or some mild steel should work good on that