Car help...what size bulb do I,need?

I want to know what size bulb I need for my 2008 silverado 1500?

I know originally my truck came with H11 bulbs but I recently installed some after market halo headlights and when I purchased the headlights it said special note "come with H1 bulb on low and high beam" im pretty sure I need H1 bulbs but my father "the expert mechanic" says I need the H11....so which ones should I buy H1 or H11 and im thinking about buying sylvania zxe or sylvania silvetstar ultra or,maybe hella xenon which ones are better? And also will I need to upgrade my wiring harness for the new bulbs?