Welcome Jerry.
There are a few of who play in the sand here.
A lot of questions to be answered assuming you have not built or owned a rail before such as:
Where will you be riding (it may be important as the the build for several reasons) and will it be a single or multiple purpose toy. Will you be starting with a new rail or massage an existing one (cost starts to come in here),
What do you plan on using for power and transaxle (IRS vs. Swing axle and AC vs. water pumpers and maybe normally asperated or huffed),
Wheelbase (where you plan on riding and the motive power come in here),
Length of suspension travel (here is where some of the differences between K&L and BJ come in)
You know, the good stuff.
Two more things:
1) I recommend starting a log/build book. Write down you plans and keep you receipts in it. Some states require receipts for getting a title which, if you need insurance for where you ride, will be important. This will also give you something to look back on when you are through and see what your trail was as to what you wanted to do and changes to that. It is also good for the next owner to know what you did.
2) You now have a string started so pictures should be forthcoming

. No pictures then it didn't happen

. Also pictures can show a lot that words have trouble describing so when asking questions they are good and the same for accomplishments.
Lee
I hope you found a happy home here.