I've used MG for 20 years and they are the best foot controlled cable motor because they will take the abuse. The light bulbs used are 12V. I'd use the smallest bulb that fits because you don't want too much heat which might melt some plastic. I found your motor parts on Boats.net http://www.boats.net/parts/search/MercuryMarine/9B304955/8168/parts.html