Can anyone describe the crimping process for installing a new gasket? I've read the threads here on the subject and looked at a diagram of the tool that's available - but I'm still not certain what to do. Is it simply a matter of pinching the sides of the gasket together to compress the u-shaped metal insert, or is there more to it? Is the special tool helpful or will a diy one work (I read about the modified gas pliers - no sure what they are)? Thanks for any direction.