Not the braking I want
Well, let's go over the symptoms described:
Also if trying to power brake the truck wants to push. Need improved front brake calipers and rotors or line lock?
This indicates that the fronts just are weak with the pedal pressure modulated so that it will still allow the rears to turn due to engine torque overcoming braking torque. The general solution to this is more front brake torque relative to the rears (i.e., a bias change) or a line lock which the OP has suggested.
But then he goes on to say that the rears lock up in normal use:
My back brakes are locking up before the fronts I noticed as well, so I ordered a proportioning valve for more adjustability
So there is clearly an underlying bias problem that can be solved by reducing rear brake force (with smaller rear wheel cylinders or a prop valve) or by increasing front brake torque.... which we have been discussing.
This all makes sense because 11" front discs and 12" or 13" rear drums that are 2" or more wide is VERY likely waaaay off balance. This is likely the issue: The rear brakes are so strong that the OP has to let up pedal pressure to get the rear wheels to spin, but at that lower pedal pressure, the front brake torque is too low to hold. If things are way off balance, my preference is to better equalize the F & R brake torques before fine tuning with a prop valve.
Now, if there is something still wrong in the fronts that are causing them to not have as much brake torque as they should, then the OP needs more suggestions one what to to check it out. I have gone through a fair list, and he seems to feel like it's good. But it is sure possible that some other item has been missed.
BTW, the pix of the pair of front pads look like the are clean to me.
