To start go to FAQ's at the top of this section. Scroll down to frt ends and read. Use the search function too. Swapping knuckles isnt that difficult it's just messy. At some point you'll have to service the knuckles anyways.
If you have a dual circuit master you want to remove the residual valve from the frt resoiviour. I you don't, you should upgrade to dual resoiviour. 79 knuckles are desirable because they are the stronger large pattern versions.