questions about 3" Exhaust setup

Hello fellow enthusiasts,

My goal in this thread is to concentrate as much information about a 3" exhaust system as possible.

**Any relevant information is welcome even if unrelated to a question or problem**
**I will periodically clean up this thread and delete useless comments or unrelated information**

I'll begin with my own goals, ideas and problems.
This all started with a lousy hole in my current stock system. Of course a simple OEM replacement repair was not sufficient. My philosophy with this truck has always been to Improve upon components once they fail. Practicality and performance are my inspirations for my titan build. A safari/prerunner style is the intended goal, but I digress. So as usual I figured I would take advantage of a bad situation and completely rebuild the exhaust system. So, The spec and configuration I've decided on is: long tube headers with 3" outlet, dual 3" cat back exhaust with Magnaflow Muffler SS 14419 that side exits through the the body panel before the rear tires on either side (The idea is to maximize clearance and possibly install skid plates afterwards) here's an example: http://chrisb.users.superford.org/Bronco/Projects/Exhaust/Exhaust_10.JPG

Now for my quesions:
1) Do long tube headers with a 3" outlet exist for titans? If yes, than which models are good quality and where can they be purchased? If no, than what would be my next best option be?

2) Besides the main components, all of the piping will be custom. Would it be better to sleeve and clamp or tig weld the system?