Cali-V...welcome to the site!!...a two-stroke 150 will be ideal on a bracket...one thing that's come up here about bracket installs...make sure you go w/a 25" long shaft motor and not a 20" short-shaft as the shorter motor will have a tendency to bury itself in the wake when coming off plane...
Rather than a new door, have you considered having a canvas snap-on cover made for the cuddy entrance?
Pictures of the conversion if ya can...we love good boat-porn around here...