need wiring help for map light

[Eclypso]

I undertook my project of adding a map light assembly into the headliner of my 98 civic LS today. I had to remove all the upper interior trim to pull down the head liner, but it wasn't too bad. I mounted the map light assembly and have put everything back together. I haven't figured out the wiring, maybe someone here can help.

My Civic LS 4D is a '98, the dome light has two wires only. One leads to the battery + , the other comes from the door switches. (I have the '98 wiring diagram) The grounding comes from being screwed to the metal frame of the roof.

The map light is from a 2001 Civic EX 2dr. There are 4 wires (see picture)

From looking at it, I'm thinking black is ground, red is (+), but there is still blue and green. Green is possibly for the door switch lead, but what about blue which is tied into yellow (thus tied to white)?

I have to make four wires become three. I'm either going to have to tie two or leave one out. Anyone have any clearer idea of this than I do?

 

[Eclypso]

As a follow-up, I decided that blue and red were both (+) so tied
them together to the (+) lead. Black was ground, green was door
switches. I wired it up this way and the map lights work, the
original dome works, but the new dome blows the fuse when I turn it
on. The new dome is what's related to the blue wire (if you look at
the picture it should be clear) So evidently I can't just tie it to
the red, although if I exclude it there is no (+) lead to the new dome
light.
Can anyone figure out how I might wire this differently? Thanks.