Thanks a million 3B!!!
That really helps.
The VIN tag on the door post is original for sure, proper rivets etc.
The GM GVW tag below it also appears original, but it states a GVW of 14,000 lbs. I wonder why the discrepancy?
To further muddy the issue, the Canadian DOT stencils on the outside of the doors says:

GVW 16,000 lbs
TARE 7,350 lbs
NET 8,650 lbs

The rear has 10 leaf springs and then another 5 above them that only come into play when the main ones are maxed. Then the other 5 rest against those u-shaped perches on the side of the frame.
The actual capacity is moot, because it is very unlikely that I'll ever carry that much weight.

Thanks again for the info.
Do you find it on a website or do you have an inside connection?

Also, the engine is obviously not the original '55 265 because it has a block mounted canister oil filter.
It could be a GM warranty, later 265, or an owner installed 283. I hope it's a 283.
I'll find out later today when I get the block casting number.

Last edited by dwightlightning; 02/20/2015 5:42 PM.