I lowered my 2000 Chevy Silverado in the rear with a "leveling kit"... this consisted of new shackles in the rear... the leveling kit drops the rear 2 inches...leaves the front alone..
The shakles bolted into the stock frame holes and look completely stock to the eye... this is another explanation on your drop... the shakles I used had holes in them to go 2 or 3 inches...
some of the 67 to 72 trucks look pretty low with
STOCK suspension.. no joke..a 3 inch from that factory height would put it down there pretty far
.....On a good note... the lowering of my rear suspension with the shakles IMPROVED my ride quality by allowing the factory springs to carry
more of the trucks weight....trucks are sprung to be able to carry weight when loaded... the 2 inch shackle drop did this to a degree and therefore
gave a more loaded and less kidney jarring ride..
... I'd give rough estimate of ride quality improvement as 10 to 20 percent...car like really
.. shakles are CHEAP! 50 to 60 bucks... anyone who torches springs freehand is a moron..
If you want a GREAT set up... Eibach makes a kit that will drop you 1 in the front and 3(shackle) in the rear... handling with swaybars will be awesome for a truck...and there will be sport engineering in your drop vs just for looks..
If you want sheer comfort ride then listen to the guys here on the drop spindles... you'll still get the benefit of lowered center of gravity for improved handling without the harshness... spindles are a really good way to go..so is leveling... so is Eibach... good luck!!