Here's a little secret also, every middleware guy I know follows a copy of the document on that Best Practices guide to setup the middleware connection no matter how expensive their bill rate. The big secret is they have read the document at least twice before starting the steps and make sure they have the answers to all the questions in the document before going forward(what are your sales organizations, number ranges, etc).
Oh BTW SAP really really really wants to you name your RFC destinations like the examples, do not put spaces in the name, follow the naming convention.
Take care,
Stephen