Wayne Parham Messages: 18752 Registered: January 2001
Illuminati (33rd Degree)
The holes don't have to be perfectly round - Just don't make them so big there's a leak on one side. Some people draw a circle on the wood and cut with a jigsaw.
What I suggest is to simply open up the hole with a file. It won't take long - MDF is pretty easy to take down with a four-in-hand.