Mystery Credits on Roy Rogers

The Roy Rogers strip was throughout its run offically bylined to Al McKimson. This name, I am told, is a pseudonym for the brothers Tom and Chuck McKimson (art and script, respectively). However, over the years I've gathered a number of additional credits from various sources. Being somewhat skeptical of art and writing style spotters, I'll just tell you what I've been told regarding the Roy Rogers strip and let you choose whether or not you take a grain of salt with it, as I do. Any additional information, or refutation of this information, is of course very welcome.

Phil Evans, writer "...the early years of the strip..." (MFG #10)
John Ushler, artist, 1949-53 (Bails)
Pete Alvarado, artist, 1949-51 (Bails)
Alex Toth, art 1960 (Bails)
Hy Mankin, art, early years (MFG #226)

One credit that is ensured is that of artist Mike Arens. He first started taking surreptitious credit on the strip on 5/10/1953, as can be seen in our sample. The detail view shows his monogram on the flanks of a horse. The monograms eventually changed to initials, and became less secretive. The art style on the Sundays doesn't seem to change on this date, so presumably Arens had started earlier, taking not even clandestine credit for his work.

EDIT (5/23/06) : Alberto Becattini sends a message wherein he discusses the credits on Roy Rogers. I'll pass along what he says:

"The Al McKimson by-line refers to Western Publishing comics editors Al Stoffel and Tom McKimson. Chuck McKimson was not initially involved in the production of this strip (which began in December, 1949), as he was at Western from 1954 to circa 1963.

Note that another Western Publishing-produced strip, Gene Autry, was by-lined "Bert Laws", from Albert Law Stoffel.

Back to Roy Rogers:

Al Stoffel wrote, besides editing, some of the first few episodes, whereas he only produced the strip from 1954-61. Phil Evans wrote most of the strip from 1954-61, and perhaps even before that. Carl Fallberg wrote some continuities in 1952-53.

Now to the artists:

Pete Alvarado probably drew the dailies and Sundays in 1949-50. Mike Arens started drawing dailies and Sundays in 1950. He drew most of the Sundays until the strip folded in 1961 (and he was allowed to sign them in 1955), whereas he alternated with others on the dailies. John Ushler drew some Sundays in 1950 (the one I have is dated March 19). Hi Mankin (he signed himself Hi, not Hy) drew the dailies in 1953-58. Alex Toth drew the dailies from Dec. 19, 1960 until Jan. 12, 1961."

I've asked Alberto for his sources for this information so that we may be better able to judge the accuracy of the above.