You may have to trim into the front mount for the core support, and maybe trim the core support. Nothing else will need to be done except to get rid of the shear pins on the steering shaft, which is common practice even when doing body lifts.
Personally, I would find a steering joint from a 79-83 to get rid of the rage joint. It will spline right into your existing steering shaft.
Buy a steering box brace kit, or build your own. I would actually brace the frame outsides as far back as possible, at least to the vin plate..