This depends on few things. What types of corals are you wanting to be able to keep? What type of lighting is the 760 watt fixture? When you say "ok" protein skimmer, what do you mean by "ok?" How much live rock do you have?
If you're wanting to go reef, you'll want to get rid of the wet/dry filter. They quickly become a nitrate factory. In a reef system, your live rock, live sand and protein skimmer take care of all of your filtration needs.
A little more information about what you're wanting to turn this tank into will be helpful in answering your questions.