Building '68 GMC K20.

[Hotrod 4x4]

Hi, im new to the 4x4 world and im jumping in all at once. Im changing the axles to the later '78s dana 44 and 14 bolt. I know the dana will bolt right up and was wanting advice on the powersteering. Will the box off the '78 bolt up to my truck? And also what advice can i get on installing the 14 bolt. It looks like i need to change the spring mount on the axle. it looks to be wider on the 14 bolt or should i change to the later spring mounts and later springs?

Thanks and have a great day...