Man, that is one serious bumper you've got on that thing! Wow! How much does it weigh? I bet everyone gives you the right of way! haha!
That is a cool looking truck! I've never seen a hood like that - what is it?
In my other posts, I was responding to a question about whether or not T. Rex Engineering uses lift blocks to obtain ride height or clearance for tires - commonly known as "lift. " We don't lift the truck - by using spring spacers or lift blocks etc. because doing so doesn't help the vehicle perform better. Now, I think you're talking about the stock spring spacers on the rear that are essentially factory engineered lift blocks. Why does the factory do that? I don't know. They spent a lot of energy redesigning the rear suspension for '03 (longer leafs, different shackles), yet they still use a stupid little spacer. I don't understand. But then again, they've got 50 engineers working full time on one part, so I'm not going to question it.
Since we're interested in performance and not looks - as I imagine you are - because you are dissatisfied with the kit you're currently using, we like to talk in terms of travel. We increase the suspension articulation in front (as you have) and use a spring and damper combo that is perfect for the truck. In the rear we stay with the stock rear springs because people want to load their trucks with nothing all the way to 2000 lbs! I can engineer a system for the rear that will work perfectly at any one weight, but not at all loads - that's why we just stick with stock rear springs and just add the superior King dampers - it's kind of a liability issue.
I would guess that your truck is not sagging in the rear. Those springs shouldn't sack out - ever. We wouldn't eliminate your lift blocks for our system - unless you've added something different than what the factory has installed.
We would sell you a system. You bolt it on (with a little drilling required - and some welding if you opt for limit straps) then tell us how it performs. If you feel it's too soft we can valve it stiffer. If you feel it's too firm, we can valve lighter in the front. In the rear, if the ride is choppy or too stiff, we have to sell you a more progressive spring, but then you have to sacrifice some load carrying capacity. It's always a compromise.
You should be able to fit 35's easilly with what you've got right now. Have you tried? They should go right on without rubbing at all.
I'll be publishing photos of what we're doing soon - as soon as we work out some marketing issues. But I can get you going in a couple of weeks if you want an entire system with King shocks.
We're going to race the Baja 500 in a Dodge Cummins using one of these bolt-on systems. We'll keep TDR posted.