So how do you convert T-12 fixture to fit T-8 tube ? 1. Ballast: What is a good brand ? Where to get them ? Any mail order ? 2. End caps: Do I need to replace the end caps since T-8 has 1 inch diameter and T-12 has 1.5 inch diameter ? 3. Starter: Do I need a starter with the electronic ballast ? Is there any T-8 tube for 18" fixture ? Thanks, Hardjono