Is it possible to change the 11john11, jacobmaate, and any other lore-friendly creator vehicles from Red and Blue to all blue lights? Tried researching but didn't get anywhere.

Yes, but I do not think that anyone currently has those available. You would need to find the lighting textures for those files and change the red to a blue by making a selection and changing the color hue value, or copy-paste the blue texture over to the red texture.

 

I believe these is a download somewhere that has various packs containing blue textures for such packs, but I have no idea where it is (its been forever)