I installed the RDE 3.0 with no issues and I'm very pleased with all the emergency vehicles, but I've noticed that the lightbar on all the emergency vehicles don't fully illuminate. I'm using the vehicle package included with RDE 3.0 and don't have any other vehicle mods installed and don't use ELS either. Only the two center lights seem to flash brightly on all vehicle lightbars. The other lights have a very dull, dim flash. Is there a way to fix this so all the lights on the lightbar flash equally bright or do I have to install new vehicles? Thanks.

Try copying all of these settings in to your visualsettings.dat which can be located using openiv at mods>update>update.rpf>common>data.

Or you could try installing radiance v which illuminates the police lights dramatically.

Sorry. I'm not sure I understand. Copying what settings into the visual settings.dat?

I think he forgot to include the settings... lol.
For now, try installing Radiance V, if that doesn't fix your issue, screenshot the lights and post it here.