The 1" and 1.6" ram pieces are machined on a lathe from bar stock then black oxided. The 1.6" ram is for the new grey or orange 20 ton Harbor Freight shop press. The 1" is for their gray 12 ton.
Remove barrel pins with a captive system that holds a hardened pin to reduce the chance of flying projectiles from other methods.
Remove the barrel with a brass block plus two trunnion blocks.
Install the barrel with either a shop press or pipe clamp.
Install the barrel pin and finish your assembly.
Removing barrel from finished receiver is possible with simple socket and extension.