Shush, Joe.
Technically, GAWR is Gross Axle Weight Rating. GVWR is Gross Vehicle Weight Rating. It only really meant something to GM and the Federales. It's the gross weight of the vehicle and what that the vehicle can hold, so 5 people, 5 suitcases, etc., may weigh 700 lbs, say, you would add that weight to the vehicle weight and there you have it. If it's less than GVWR, you can pile them in safely. USUALLY it's around a little over a ton in front and a ton in back for G-bodies.
But this varies on each car...a little. Each has a base weight, but changes as options were added. I haven't taken any time to delve into that because who really cares anymore?
Depending on options and other things, the GVWRs comes in individual flavors. GM used a "guide" to determine the effect of GAWRs for each option. In the real world, they do have a general range. Unless you have the actual build sheet or any other paperwork that shows the front and rear axle weights, you won't really know for certain.
And how many people REALLY look at it? Most owners that worry about getting the right data on their door jamb decal for their vehicles are long past going to ever overload it. Unless you win all the trophies at every car show and carry them in the trunk.
My guess is this load is exceeding the safe GAWR RR for this truck.
I have a slew of examples of GVWR decals.
My recommendation- I picked out a car's door jamb that had T-tops, but that doesn't make a lot of difference. But here's some numbers that's in the ballpark:
Use GVWR number of 4435 LB/2035 KG. (basically adds the two GAWRs together, although there are some examples of this being off just a bit)
Use GAWR number of 2277 LB/1033 KG for the FF.
Use GAWR number of 2208 LB/1002 KG for the RR.
You will be fine.
Here's a loaded out 85 442 T-top car decal with my own reproduction draft next to it (my own car). It's a Salon base, which is a tad heavier than the Supreme. That's why I said go with the numbers above and you'll be fine. My 85 is one of those examples where the KGs don't add up, yet the pounds do. Rounding? The 87 decal is a bit different, but my 87 doesn't have T-tops.
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Here's another 87 442 decal from a January car. You can see the numbers are a bit different, but not all that much. You could even use these numbers if you want.
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