OK, Here goes.
Son and I are re-building a '79 f-150 4x4 quad front shock setup, frame up. Found another 79 for parts, single shock front setup.
So what I have found so far, is that the re-build truck has what looks like 4" factory blocks in the rear, below the springs, and the DONER truck does not have these blocks.
So, which truck is stock?
My Dad bought the quad shock truck back in the mid 80's, as far as I know was never lifted, reason for the concern is that the shocks that I bought are to short.
Thanks in advance for any help,
Smitty

 

AFAIK, no trucks after 77.5 had any blocks in the rear. The pre 77.5 4wd trucks had blocks in the rear to level out the truck to match the "lift" caused by the transfer case and front axle configuration.

Factory blocks have a bump stop horn to the inside of the block. Most aftermarket blocks do not.