FL...
It will depend on the aircraft weight, and whether you go on a Tango or not. Tango's are MNPSA (see here: [URL="http://www.thelandingstrip.org/files/MNPS%20Ops%20Manual%20v9.pdf"]MNPSA[/URL and so you could be at whatever level is available for your crossing - it's never guaranteed.
For our operation, generally we are between FL360 and FL390 (depending on direction obviously) as the weight decreases. If we are on T9 / T16, then you sometimes have to climb or descend for the crossing.
As I said, if you ask and do get to pop up ahead of the flight, I'm sure the crew will show you the route, levels, etc. If I have people who are really interested, I often give out the paperwork we don't need to keep after the flight.
DW.