Need help swapping to DRW

[Storm Chaser]

Just got this truck a couple weeks ago- 78 3/4 ton 2 wheel drive with a flatbed. Just got the engine and tranny installed in this old beater, and decided that I want to convert to a dually. The rear end is taken care of- the axle change is pretty straightforward. My confusion lies in the front...

According to what I found on car-part.com, a local yard has a set of rotors from a 92 GMC HD van (read:short bus) that is supposed to be the same as the rotors on a dually truck. A quick check through Autozone verified the part numbers are the same. Next, I queried autozone for wheel bearings and found out that although the bearings for the van were the same as for a dually truck, they were NOT the same for my 3/4 ton. So, that leads me to believe I need spindles. I typed "1 ton spindles" into car-part.com and that van showed up in my list again. Just for the heck of it, I searched control arms (both upper and lower) and it shows 3/4 ton and 1-ton as using the same parts. The confusion starts when an owner of another local yard swears that those dually van rotors will go with my current spindles, despite the zone's calling for different bearings.

SO, I guess, here are the questions...
1. Am I right to assume that I need the spindles to go with the rotors and that mine won't work?
2. Can someone verify that those van parts are in fact interchangeable with 1-ton drw truck parts?
3. Although I couldn't find a definite answer after hours of searching, are the 1-ton spindles a bolt-on with my current control arms?
4. What about the tie rods? Same from my truck to the new spindle?
5. What do I have to do for the brakes? Are the calipers/mounting brackets the same/different?

The only reason I am stressing over these van parts is that they are in great shape and I'll be getting a pretty good deal on them. Thanks in advance.

[pig rig]

ok....... follow along

3/4T spindles are different then the 1T srw and the differance is how the brake calipper mounts
but 1T spindles are the same for srw and drw trucks
3/4T rotors are not the same as 1T swr rotors and drw rotors are different then both
1T srw and 1T drw calippers are the same and 3/4T is different
woo....

ok, balljonts are the same for 3/4T as for 1T srw and drw
and arms are the same for 3/4T and 1T

and none of this stuff interchanges with a 1/2T

[Storm Chaser]

I don't play with half tons... I like my trucks

I kinda figured from what I found on the net that my current 3/4 stuff is out. Since the ball joints and arms are the same, I'm just looking at changing everything from the spindles out, right? I just found on the Zone's site that the outer tie rod ends are the same, so there's the steering.

Now I just need to verify if the spindles from the 92 3500HD van are the same as 1-ton drw spindles (the van is a drw vehicle). I can't seem to find anything online other than car-part.com that will verify this for me.

[pig rig]

I don't think so I went out to see if I had a set of spendles to get the part# off of them so you could check that way. but no luck

was the van updated in 91 with the crew cabs and suburbans or did it get changed in 88? that will tell you see how far back those parts fit the van

[Storm Chaser]

Here is the vehicle in question...

I don't know what year they changed body styles, but being how this is a 3500HD, it might have been like the trucks where the body style changed, but the HD's still used the old one.

Anyone have access to a Hollander? I just need to know if the spindles from this thing are interchangeable with 73-87 1-ton pickups.