Hi Bogert, welcome to the forum
I'm not too sure about the structure of training in Shingon or where it takes place, but I have to say that being a priest is a big commitment and not one taken lightly. Although Priests in Japanese Buddhism can continue to be married and have jobs, social lives etc you will have to give up some of your time to the role and to training, the latter of which will require you to take time off work. All of this could effect your relationship with your wife/children/family/friends etc.
I hope you find what you're looking for.