How do I optimize this database design?
I expect this model to be a bit more complicated than two tables. If the vehicle tracking provides you with two IDs, then they may probably be foreign keys to some specification. Also, it is entirely possible that different vehicles will have the same hardware, and the other way around, different hardwares will have the same vehicle. In that case, you need to normalize it by placing in different tables.

My proposition is based on the following model:



EDIT

Thanks to @DamirSudarevic I've made some updates in the model.