In 1972 Frank Tunney ran a series of shows at the Ontario Place Forum between May and October.
There were 7 shows set for Thursday evenings over the course of the summer with the last coming a few days before Ontario Place was to close for the year.
Three of the first set in May and June filled out the 3,000 seat Forum with another 1,000 or so on the grass slopes surrounding the structure. The first show of the second set, held on Sept 6 drew 1,200 due to rain being forecast. It did rain keeping the spectators that did show up under the roof and off the grass.
Other shows were held Sept 14, 28, and Oct 5. Tunney was said to get expenses from Ontario Place, his bonus being the calling of attention to his Sunday night spectaculars at MLG.
Sept 6 results
Lord Layton defeated Joe 'Killer' Christie
The Love Brothers beat Nick DeCarlo & Tarzan Zorra
Tony Parisi over NIkita Kalmikoff
Lee Henning drew The Beast
Jeannie Baxter drew with Vivienne Lynn
I saw quite a few concerts at the old Forum starting about 1977 but never caught a wrestling show there. Thought they held more shows over the years but have yet to locate any.
The 1972 ones are the only ones I have found as of yet. The Forum opened in May 1971 but unsure if they held wrestling that first season..
Jun 29 below, below that is May 25 both versions, the others are just small ads, no listings