I just bought a set of the JDM MR Headlamps to put into my 2003 Lancer Evo. I was told to buy a different wiring harness for the foglight. So I did and now I am having a problem. The factory US foglamp does not fit into the housing. I was wondering if anyone else had this problem and where they got the correct size bulb. I also noticed there is a small lightbulb that goes into the housing that I don't have either. I was told this bulb in Japan is there to light up the housing when you have the parking lights on. Just to illuminate the housing. The place I bought them from doesn't have a clue. Any information would be helpful. Thanks

 

you need to snip the fog light sockets out and replace with 9006 sockets.
Can get those at checkers for about $3.50

 

Is that the only way to do it? So I can't buy the correct bulb with the right socket.

 

Like he said, a 9006 bulb fits the JDM housing for the foglamps; the stock US ones don't.
So buy a 2-pack of 9006 bulbs; you can get them at any auto parts store.
You said you already bought the harnesses.
If so, you need to cut off the US stock foglight connectors, and connect the 9006 harness.
Then just pop the 9006 bulbs in and plug the new connectors onto them.
I do not know about the small bulbs...

BTW - before you install them do yourself a favor - readjust the lights to shine towards the right.
They are factory aligned to shine towards the left, for LHD countries.

Here is a pic of the screw to turn.

Tighten the passenger side to pull the headlamp to the right.
Loosen the drivers side to push the headlamp to the right