Whats the best way to locate a leak?

[66KingFisher]

Well, it seems we've developed a leak in our little Basstracker.....until recently, when we pulled the drain plug it was always bone dry, but suddenly we've been taking on water...not a lot, but enough to cause concern. We've raised the boat off the trailer and looked all around the hull and found nothing...no damage other then some very minor scuffing and scratches non of which appear to be deep enough to cause a problem. All the seams are welded so rivets are not an issue, and other then the inlets to the livewell and the drain plug itself there doesn't seem to be anywhere for water to get in. At this time I think our next move is to remove the front deck area that will allow us to see the plumbing going to the livewell and pump to see if something there has come loose, but otherwise we are at a loss as to where to check next or what might be the best way to find the leak...Put the plug in and fill the boat with water and see if any leaks out is all we can think of....Any other suggestions guys?