[69GMCLonghorn]

Obviously if you're up for a project like this, you're not opposed to doing some fab work, etc, which I applaud since I'm not at that point yet... I will start by saying I think it is a great project, but keep in mind, there's a reason they don't shove diesels in 1/2 tons; most of them can't handle the torque. But I'll bet you can make it happen. Here are my suggestions on what you'll have to beef up:

What I would do is get the engine/trans and set it in the front end and get the weight on the frame. See how much it drops. Have a set of springs made for the front end that will support it. A good spring shop should be able to calculate what is needed.

Because of the extra weight, you'll want all your front suspension/steering components in the best shape possible. Maybe upgrade to urethane bushings, heavier duty ball joints would be a must, new idler/pitman arms wouldn't hurt either, and the biggest freakin' sway bar that money can buy!!

Check your wheel bearings and make sure they are good, too. Everything will be working harder to move/support/turn/stop that weight, so whatever you can strengthen, do it!

My guess is the frame will hold the weight as long as your engine mounts are good. The more power you generate, the more things will need to be stiffened. But you can play it by ear and see how it is after you get it running. If it flexes too much, look into adding some X members or whatever.

as I stated, all the more power to ya, but I'd personally do this project with a 3/4 or 1 ton, just for the added strength...