What I'm about to post is just some frank advice and food for thought. You know you and your circumstance better than me or anyone else, except the Lord. What I'm about to post doesn't even require a response from you, either. I just hope you consider it, and whatever worth it has in your mind, act accordingly.
After reading your initial post as quoted above, I had two thoughts:
1.) You're already ministering full time
2.) Anyone at your job hear the Gospel from you/won anyone from work to the Lord?
The first thought is not so significant, at leas to me, but to say that it's entirely possible to minister and serve in the Kingdom of God, have a burden to do more, experience the passion and zeal to work for the Lord, and think it means you have to drop the job and hit the road, so to speak, in order to minister "full time" when all along you've already been doing just that.
As to the second thought, I am of the opinion, for whatever that's worth, that the station we find ourselves in, is the place God wants us to work the most. For almost everyone, especially men, that station is the workplace. That's our fishing hole, or our vineyard, if you will. If we aren't working there taking care of God's business, it's pretty presumptuous of us (I think), to say to God, to ourselves, and to others, that we'll take care of the Lord's business, just somewhere else, as soon as He decides to let us off the hook.
But if the workplace has been evangelized, and all the fruit you are ever possibly going to harvest has already been harvested, then I see God moving you along to a new venture, whatever it may be. But not before.