Post #17 in this thread

http://www.poolforum.com/pf2/showthread.php?t=261

should have links to a couple pics for a pressure test jig and a description.
If the pics aren't visible for some reason let us know and we'll figure something out.

On a patience note, for a couple spring seasons I've chased my tail thinking I have a leak and it indeed was evaporation. Simply caused by warmer water, cool dry nights, and wind. You'll be surprised how much water can be lost.

Al