If that step-by-step instruction above seems too complicated, the basic principle is: Mark the same two points in the show in both recordings, measure the time distance between them, divide one length by the other to get the ratio of the two, then either slow the recording that's shorter or speed up the one that's longer by that ratio to get them to match.
The trickiest part is finding the exact spots to use as markers: a snare hit is usually good since it's a nice sharp peak, but it could be anything that's easy to identify in both recordings. After that it's just simple math and the use of whatever pitch/tempo tool your editing software offers. (If you're not sure whether you should be multiplying or dividing by the ratio of the two, just try one or the other and see if the distance between the two markers ends up the same in both recordings — if not, go back and do it the other way instead.)