Welcome to NICO, Tiekie. There are a few of us stone-agers around, so you're in good company.
Sounds like you've got quite a project on your hands. As our rather blunt posters above mentioned, we have a pretty sexy search feature on the forum and that's going to be your best resource to get the information you need. We have forums specifically devoted to the RB engine series as well as the S13 chassis. Between the two and the search button, I guarantee you'll find others on here who have done this swap before and can give you useful advice.
Post some pictures of your car when you get a chance. And again, welcome!