[1.8.9] Independent transforms for parts in a custom models

Greetings, I am working on rendering a compass item using a custom OBJ model. I have a model class that implements ISmartItemModel and I am creating an IBakedModel in the handleItemState method. I create my OBJModel.OBJState using my List<String> of the parts I want to show and then I can create TRSRTransformation with whatever I need and then use that stuff to bake the IBakedModel that gets rendered. I can't seem to figure out a way to apply the transform to individual parts, using this method the transform is applied to the entire model. My model only has 2 parts, the base and the compass needle. I want to rotate the compass needle on a single axis based on a float value that is saved in NBT to the ItemStack. So my question, is there is a way to apply transforms to individual parts of a custom model?

Thanks.