I have no collector's interest in a Randall, have at it. I can see where a 4"+ gun would aggravate a bullseye shooter.
You might look into the Cash Gustin system; setscrews into the locking recesses to V-block the barrel into alignment. No heat.
Otherwise, weld away. Do you have means of cutting the pad to fit?
Caution: I am not a gunsmith making professional recommendations. Just happen to have read some stuff along the way.