I've been reading information at various blogs and such, which helped piece together who worked on the strip, but not exactly when. So many of the artists worked in the "J&C" house style, so when one took over from another, to some degree, they tried to make it look the same. Even so, some artists' styles come through anyway.
Despite my having so little George Evans in my collection, his was the easiest to spot, partly because I had 2 pages of his already at my blog (SVTU). The Lou Fine period is the hardest to I.D. Everyone who's commented has said that nothing of his style is evident in the art! And several people have suggested there may be a few other people involved in the "Lou Fine" strips. I can believe it, some of them look very different, and there's that one that keeps making me think of early Gil Kane. (Then again, considering Kane always said he was influenced most by Fine, it's possible that strip may be one where Fine's own style came thru the most.)
After reading about Al McWilliams (in the ALTER EGO article a few years back and since then), I naturally figured the stuff from '68-'69 I read way back when was his. NOPE!! It was all Gray Morrow.
In both cases where Fine took over, he tried to keep it looking like the artists he replaced (Evans, Morrow), but I could still get a sense of what was theirs, and what wasn't. The Fine stuff was just missing the "feel" of their work. It struck me that the last batch he did, especially what I believe was the final one, look like he may have been in poor health when he did them. All of a sudden, the style changed again, and it took me a bit to figure out... HEY, WAIT A MINUTE!!!-- that Morrow had come back.
Someone at Captain Comics pointed me to a French website devoted to MARS in sci-fi. Some of their info matched mine, but a paragraph on the 2nd half of the run was completely wrong. It's nice to know that, despite what I've done being a lot of guesswork, I feel fairly secure that my info is more accurate than theirs.
Now if only I had some idea who worked on the STORIES FROM THE BIBLE series...