1. How hard is it to replace the side marker lights on the IS300 with LED BULBS and change to clear lens?

2. How about the tail lights as well?

 

I'd be cautious about using LED bulbs in your taillights. LEDs are very bright when viewed head on but their brighness is dramatically lower if viewed from the side. Your reflectors are designed to reflect light from every direction to get maximum illumination, LEDs dont cut it unless your housing is designed for them.

 

"I'd be cautious about using LED bulbs in your taillights. LEDs are very bright when viewed head on but their brighness is dramatically lower if viewed from the side. Your reflectors are designed to reflect light from every direction to get maximum illumination, LEDs dont cut it unless your housing is designed for them."

What about the sidemarker lights?

 

I've seen some pictures where they looked ok in the sidemarkers, but I've never seen them in person in the sidemarkers.