MG ZR universal central locking?

hi i have a MG ZR 2002 and the cheap bugger how bought it from new didn't have the central locking installed, i have found a kit on ebay, but what i want to know is can i wire it to work with my existing (OEM) key fob? i have had the door Panel of both sides (penger side no motor or wires) drivers side has around 4 wires going to a modual that when i lock the door by key it activates the alarm, i also know that yes i can run it on the new fob but i will lose the luxury of the interior light coming on when i press the OEM fob, i know its petty but i want to use the OEM fob as this also activates the immobiliser, has anyone got the wiring diagram please or a rover 25 zr haynes that they can scan and send me the required pages thanks