6 hours layover in YYZ
I'm flying FRA->YYZ->SFO and I have a layover of about 6 hours in YYZ. I'm arriving on a Monday at 12:15pm and departing at 6:30pm. I travel light, so I'll just have a carry-on.
A few questions:
1) How long does it take to go through Canadian customs and immigration at around 12:15?
2) How early should I be back at the airport (I have a US passport)? Air Canada suggest 90 minutes, is that enough? Does it help that I have *G status?
3) Any suggestions on what to do? I'm not really into shopping or dining. Sightseeing recommendations would be great and I'm willing to rent a car if it makes sense.
Thanks!