440 / 727 swap in a 73 duster

Professor Fate said
Pretty sure you're looking at a custom exhaust then. NO factory manifolds will fit a RHD big block A body, and header selection may be limited to only a couple of Aussie-specific offerings, if any. But I'm sure you've got that covered.
How are you converting the steering, bolting the Aussie box to the RH framerail (will need reinforcement), or going rack & pinion?

I was definitely gonna go with a rack and pinion set up, just not sure whether or not to go a power rack setup. I want to be able to turn the wheel easily but still have a good feel through the wheel. I haven't had any experience with power rack setups before.