1) I have the Garden Gate TH 2.2 miles (not 2.7) from Drake
2) I'm pretty sure the blue trail in the panorama is the Gravel Pit route, not Garden Gate (GG Trail would be entirely occluded by the distant ridge on Crosier as viewed from Triangle Mtn)
for catching the discrepancies. I fixed the picture or at least, made a note. As far as the mileage, I'll drive it again in a few days & get another total.
There is parking for up to 8 vehicles across the road from this trailhead. Simple roadside parallel parking, but space for several vehicles.