Curious why you wouldn't want to stick with that era frame. If you go to a '72 frame you will have 5 bolt hubs, disk brakes, power steering, and if the trailing arms are in good shape they actually give a pretty nice ride (in my opinion). I'm doing a ground up on a '72 right now and I'm using the original frame.
Just a thought.
By the way, WELCOME TO THE 'BOLT! Now that your'e a member, you'll get hooked by the forums and you won't have time to work on your truck anyway! HAHAHAHAHA.