[ThatGuy]

The H4 is your High/Low.

The H3c has been disputed as either a fog light, or a supplemental high beam, meaning when you click on your high beams, all four lights should be on.

But bottom line, DON"T put HIDs in bricks. They were NEVER designed to have HIDs in them.
Swapping proper projectors into them would be better for light output, but it would look horribly goofy.
If you want to do a HID projector swap, then start with a set of dual or triple projector lamps.