jeez guys, the whoel schedule is on renoscca.com 
http://renoscca.com/events/2006/04-29%20TT%20Flyer.pdf
Drivers meeting is at 8, gates open at 7, so I'd say get there as close to 7 as possible.    Race cars on track at 8:30, followed by Advanced Club cars at 8:50.  And so on.  Then alternating all day.