One side is easier than the other but I think that has less to do about the bulb. After they lock in place the chips should be facing up. You need to fit them in a little off center and it’s less than a quarter turn. There are a three tabs that line up the same as the stock halogens and the trick is to line them up the same.Did you have any issues getting the Twelvolt’s in? I tried today and Gould not get them to seat deep enough to be able to twist lock the tabs. Is there any tips? Tricks? Or secrets?