I think they are 3.5" to fit in there right, but it's been a long time since i've measured. They have some at walmart or auto zone that would work, but the bracket that comes with them is very difficult to install right. I ended up getting some from a local import shop for $90 that came with much better brackets. Unfortunately, you won't see what they look like until you open the box... Just use round truck lights. I just hooked up the new wires to the old fog wires to still use the controls on the light switch. it's really simple.