Most importantly: why do you care??
No need to measure, but the size of each "channel" is roughly 1ft, maybe 10". So if reference is at the center, you'll get a range of: reference +/- 10" (5" to each side).
Think about it... if reference is 20".... is your stance likely to be as wide as 30" or narrow as 10"?
Nope. You're likely near reference, so don't worry.
Edit: lol hadn't read poutanen's post. So yeah, what he said.
Last edited by F1EA; 04-10-2014 at 10:40 PM.