Sealant around vin tag

[hemi43]

Here's mine, original paint 1970.

Since we are on the topic of VIN plates, has anyone ever noticed that the GVW for 69-70 is only 5000 lbs, yet 71-72 is 5850 lbs?
Where did they pull the other 850lbs?
This might not seem like a big deal, but it is. My truck empty weighs around 4800lbs, and I'm 220lbs. You do the math on this.
How were these trucks even legal?
GVW (gross vehicle weight) is the maximum the truck can weigh including fuel, load and passengers.