Improved calipers and master? Never heard of that. I finished parting out an 04 last summer and they didn't look any different to me.

 

Firstly set a reasonable budget. Find the best stock unmessed with truck with the lowest mileage available and preferably not over 100K miles. Take someone who knows D2's with you to ensure the frame is good and all the dash lights come on and go off accordingly. Now the real important bit, drive the truck around and watch the temperatures and listen carefully to the gearbox and engine. When the test drive is complete check the truck for codes with a diag, but never go to look at a truck without a diag: tool, it's the fastest way to waste money. IMO never buy anything but a stock truck as bolts on's confuse the quality and ride and are sometimes built by idiots. Never be in a hurry to buy or you'll end up with a dunger and there are thousands of D2's on the market.

 

I'm yet to still find a 2003-2004 at the wrecking yard to check it out myself. I've been fighting with my brakes since I got my D2 and that was one of the suggestions made to me about improving braking. My master cylinder when I was purchasing one from Atlantic British noticed they have a part for 99-02, and then another for 03-04. I was planning on just changing the front calipers but was told I had to do the master as well off the newer D2s to get the improvement. Now you left me wondering...