You don't need to drive there. There's a streetcar that runs east-west right past it, and a bus that runs north-south. In my case I walked there and TTCed home.
Yes, the giant above-ground garage is oddly designed and there is not enough signage yet. More signage won't solve all the problems. You don't have to take stairs; there are elevators, the size of bedrooms.
Drivers will figure out soon enough how to go east on St. Clair when leaving the lot, but…
Yes, traffic in the area is bad, and this place will only make it worse. The St. Clair streetcar should never have been given a separated right-of-way through the underpass until the underpass was widened (which all should have happened at once). Keele, I dunno how to fix. The area should get a station either on the GO line (after CityRail-ification) or the DRL west subway extension sometime in the future. Good luck until then.
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