you're talking about a very small amount of price difference. Just wait and do it properly.
People always talk about adding extra sealant to it when you put it back together. I have cleared/opened 12-15 sets of lights and NEVER added extra sealant, and NEVER had a leak. When you open them, pull the cover "straight" off the housing so the OEM sealant doesn't get disturbed more than it needs to. Then reheat when you put everything back together and apply even pressure. You will be just fine.