hemi swap rear end

I am planning on restoring my 72 duster and adding a 5.7 L hemi and have a couple of questions. Currently I am collecting parts and working on the body.

I may cut down a rearend from a truck for a dana 60 or 8.75. Would there be any advantage in changing the axle offset or stay with the stock configuration? Still penciling it out at far as cost and advantages.

Would a salvage durango have the truck motor and proper auto trans?

What is used for the gauges and speedometer could I make a dash from the gauges in the salvage vehicle?

I want to make this a budget build so I am not planning on the alterK at this time. Currently I have the slant six K frame, will this work or is there a better K frame to utilize? I have the control arms off a 74 valiant and the front spindles and brakes from a volare. The duster currently has power steering and I may try adding a rack instead. I am hoping in the year or so it takes to finish the body they will have a good option for an A body rack. I would prefer power steering if there eventually is a way with the stock K frame.

Thanks for the help.