Do I need to replace my light gasket?

I just purchased a brand new Pentair Amerlite 500W light to replace an old one that’s falling apart.  Before installing or using it I’m going to replace the incandescent bulb with a 12v LED RGB bulb (I will be installing a 12VAC transformer as well).  Do I need to replace the gasket after opening the brand new light to replace the bulb before it’s even installed/used?