Super Blackhawk long grip frames

[chet15]

I have recently come to the conclusion that all Super Blackhawk long type grip frame castings were probably cast with a narrow trigger slot originally, which goes along with the original description of Elmer Keith's "first pilot model" of the Super Blackhawk in his 1959 "GUNS" article. When Ruger decided to put the wide trigger in the Super Blackhawk (i.e. prototypes 15527 and 15528), the company just milled the trigger slot wider.
I would be curious, if anybody has a Long Frame super apart, to see if their trigger slots are indeed machined out?
Also curious on an early short frame super if the wide trigger slot is indeed cast. You can tell if it is cast or not with the pebbled texture of the surface. Machined definitely looks machined.
Chet15

[Mike722]

can't say for sure, but without taking mine apart, it looks like it has been milled wider, not cast.