hey Guys,
I would to start off by saying thank you to all the individuals that have added information to this thread. With that noted, I feel that it is time to share my experiences with DT v8 headers.
Step 1, purchasing the headers: After doing a good amount of reading and deciding that tundra headers were going to be too much work, I started searching for a set of DT headers for the best possible price. What I stumbled upon was a company called Colorado Speed that was selling the 05-09 headers for $674 with free shipping. Needless to say, I ended up purchasing a set from them. I feel that its a good time to note that these headers are made per order and take 1-3 months to receive the product "absolutely worth the wait".
Step 2, Purchasing the little parts: due to the fact that I live in Wisconsin, utilizing that factory cats was not in my interest. As a result, I decided to run 2.5" .065 304L stainless tubing in the location of the cats. As most of you guys know, we still need as flange at the bottom of the down-pipes to tie back into the factory exhaust. This was a difficult item to find because A, I wanted 304 stainless and B, I needed a flange that would bolt up to the factory exhaust but also remain 2.5" for when I make my new exhaust. ACERACE parts ended up to be the perfect one stop shop; flanges, tubing, and gaskets all in 304l.
stainless.
Ace Race Parts ? High Quality Fabrication Components
Step 3, Hardware: I don't think I need to go to far into detail on the headers hardware because previous members have posted the part numbers. This can also be found though your dealer for a premium price.
Step 4, Disassembly: Ohhhh the most dreaded part of the entire project. My truck has 110,000 miles so its just a baby. Needless to say, I was still worried about frozen bolts because all the difficulties other members were experiencing. To my amazement, there were no broken bolts or issues of any kind. "IMPORTANT" take your time with removal of the old header bolts. Find someone to give you a helping hand and make sure your socket is completely on the nuts/bolts that are being removed. I lucked out and had all 16 bolts extract with the nuts. I found that the top bolts were easiest to remove with a breaker bar that has a head capable of rotated a little past 90 degrees. The lower bolts I found that the best way to save skin on you hands was to put the 1/2" impact on and just give-er
Step 5, Welding and test fitting: Due to the fact that this is not an inexpensive project, I had my buddy TIG weld the collector and flange. This process was greatly enhanced by building a jig around the old headers and simply mounting the DT headers. By utilizing this process, Absolutely no welding took place in the cramped engine bay. Just to be safe, we tacked both headers and did a quick test fit to make sure all was well. I would like to thank the individual the gave me the great idea earlier in the thread. No problems with the jig, Joe was a happy guy.
Step 6, Final installation: Looking back, the final installation was the easiest and most gratifying part. Install the header studs, gasket, and slide in headers. The one thing that I recommend to you air injection guys 05-09 is to install that air injection bolts once the headers are in the truck. Simple and easy.
Step 7, Post pictures for all the guys that really hate reading. 
