Upgrading our lighting to LED bulbs. Have most of them installed. Trying to replace the RG 1141 bulbs. Was asked the polarity because they have 2 polarities for this bulb. I told her that all I knew was that the Denali TT 2006 was negatively ground. Can some one explain this to me. I know if the light doesn't light the first time I install the bulb, that I should flip it over and it should work. Is there something else I should look for? Sort of new at this.