Here is a good guide for you guys.
http://www.indymotorspeedway.com/index.html
I am not sure you could get to Gasoline Alley and back
before the race. Don't think I would try that. There is
so much on track stuff going on, marching bands , pushing the cars out,
celebrities milling about , etc. etc. Before you know it the
balloons are flying. I would get to the seats and set up camp, then
work your way as close to the fence as you can for some pictures.
Last thing you want to do is get caught in a bottle neck somewhere
with 10,000 other fans when the green flag drops.
There may be a tunnel you can take to the inside of track from the front straight.
Check the maps from the above link.
There is a slim chance there may be a gate open on the front stretch
to cross the track. Saturday is your best day for Gasoline Alley.