For an 1.25" kit you will be fine with the shifter and steering. You will need to make some brackets to lower the radiator fan shroud. You will also need to cut down/ make spacers for the corners of the grill. The best advice I can gove you is to start hitting everything with PB Blaster. I was lucky I only had one body bolt break off and it was the easiest one to access, the one under the passenger side fire wall area. If the ones in the back near the tail gate break off, well lets just say it is not an easy task and requires cutting some holes to get access to intall new nuts.
I would recommend a 1" MML if you plan on a belly up skid. You will need the room.
Are you going with the D300 flip kit? If so, which one. I eventually would like to go with a D300, but I can't justify 2 new driveshafts when my NP231 and rear CV shaft is still in good shape.