Were the episodes from the "trial run" week (September 1975, I think) ever rerun on GSN? The "Big Wheel" was just a standard-sized clockwise-spinning wheel back then.
September 8-12 (#158xD), and as far as I'm aware the earliest Season 4 episode GSN aired was the first permanent hour show.
Barring a master copy of #1581D (with a serious quality drop for the second half), nothing from that period seems to have showed up in any form until the DVD set's #1585D, #1651D (October 27), and #1652D (October 28).
(As an aside, the staff doesn't seem to have felt too confident in the experimental hour format -- the slates for #1581D and #1585D have a message held up by a stagehand once Johnny finishes, with #1581D's being something like "Welcome aboard the
Titanic!" and #1585D's being "This is #5. We made it. AMEN!" {to which Johnny replied "Amen, brother"}.)