I want to upgrade my headlights to 90/100 bulbs and need to upgrade the wiring as well.

I am good with wiring and understand relays as well as they can be understood I guess. I am a little lost on diodes and resistors though. If I make my own harness using relays, are there any diodes/resistors anywhere that are going to have to be upgraded as well?

It seems that I remember reading there are but now I can not find anything anywhere that states that.

Anyone have some link or thoughts.....

 

Buy the 4crawler harness, its like $40 and its plug and play...

 

And his website will help in understanding how the Toyota lighting circuit works, too.

 

heck, i think that he even has instructions on there for making your OWN harness...
if you are that mechanically inclined, that is...