59AB question

[Sod Buster]

On the forward end of the block, drivers side is a petcock, what is it for, pic below.

On the passenger side looks like a heater hose connection, it has a handy same size bolt crammed in it at the moment as I have the block full of Evaporust, soaking.
The car also had the T insert in the lower radiator hose for a heater hose connection.

 

[Ken/Alabama]

Should be a petcock in each side. They were used to drain the block .

 

[Sod Buster]

Should be a petcock in each side. They were used to drain the block .

There was a funky old block heater hooked up to the passenger side, so no petcock on that side, I was hoping I had found a secret whiskey stash.

 

[RKS.PA]

Sod, I'd be a little careful testing the "secret whiskey stash"....might affect the eyesight you'll be needing for the rest of your rebuilding project!