I'm not around DFW, but, don't sell yourself short. Tell us a little more about exactly what you want worked on and you may be better equipped to handle some of it yourself than you think.
Lots of great help here in the board.
I also doubt you really want a one-stop shop, let alone will find one for all those things if you want the best work at the best price.
Interior is easy to take apart with hand tools. You can refurbish/recover some stuff at home, others really might take a good upholstery shop - which is a different skillset than a drivetrain swap.
For suspension, the quality of parts used means more than who does is. Economy parts store vs durable higher end professional grade components makes a difference in how well and how long it lasts.
Your engine trans we would ask carb or fi to start, there are a ton of guys here very knowledgeable having done those swaps (personally I'm more of an older tech and swap type).
But do tell, more details on what you have and are tying to fix, sounds like a fun project!
ck80 and everybody else, thanks for the informative replies.
I agree that I can probably acquire the skills to do a lot of what I want with the EC, but I literally just don't have the time to do it. I own my own business and work 10-12 hours a day, sometimes 7 days a week. Once I start the project I will want it to be done in a timely manner, and if I did it myself that would never happen, especially considering the learning curve.
My mindset of a "one stop shop" comes from my experience with trifives, x-frames and Camaros, all of which I have owned or still own. Specialists in those cars tend to be most skilled at a wide range of systems (be they OEM or mods) that pertain to those models alone, with the possible exception of upholstery. So it might be good advice to seek the drivetrain work from one place, suspension mods from another, and wiring work from yet a third, when it come to G-body cars.
The Vortec is a 5.3L FI from a 2000 GMC Sierra, as is the 4L60e transmission. I know there are quite a few kits out there for installing exactly this drivetrain in a G-body, such as Muscle Rods
http://www.brphotrods.com/products/78-88 G body products/index.html (and many others), as well as a lot of choices for individual pieces that are not part of a kit. But I have no way to judge if one is any better or more suited to my specific needs than another. I do not want to up the performance of the engine or trans, just regasket and reseal them, as they both run extremely well without any issues, having been well maintained and cared for (I bought the GMC new).
I have already read dozens and dozens of threads in these forums and have learned alot. There is a great knowledge bank here and I will continue to mine that vein and several others, as I try to gain more info about what is possible and refine what I want to do to the EC.
Thanks again guys.