Doc,
like what sir av8or5 said, kayang kaya i-DIY ito... lakasan lang ng loob... one mistake sorry..... para ka lang nag ooOdontec niyan.... hehehe steady hands for the incision.
way back when i still have my Sentra GTS ako lang din ang nag kabit ng map light nun... what i did was i traced the shape of the map light into a cardboard, from there i cut the traced lines from the cardboard and test fit the map light. after im satisfied with the fit, i then used the cardboard as my template. after tracing it to my head board,

patigasan nalang ng dibdib and pray that you dont over cut it. dahil kung masydo mapalaki hehehe laglag ang maplight...
with regards sa wiring tap mo lang yung positive sa cabin light and ground it sa body. thats it...
hanap ka nalang ng maplight...
last time i asked sa casa its 4K na daw....