magnum manifolds

Gents,
I am currently having my 360 engine rebuilt for my 74 Duster (Manual steering/brakes and floor shift auto) and making preps to reinstall with different exhaust. Previously had a set of long tube headers that had been badly scraped on ground by previous owner and damaged. I liked the sound/look of the headers but didn't like trying to work around them all the time and the heat they generated.
I am thinking about shifting to a simple set of manifolds on re-install of the engine as I primarily just cruise in it (and lay some rubber once in a while). After researching at Summit Racing for a set of the stock, HUGE, log-type car manifolds, I found this thread and much prefer the shape and look of these 90's era magnum truck/dakota style manifolds. From what I read above, I believe I can expect these to fit on my Duster w minimal problems. IS THAT RIGHT? The Dorman brand manifolds I found at Summit are listed as having 2-1/8" openings which seems reasonable to me.
Any advice? Anticipated problems? (I did see Stephen's note about potential contact with trans dip-stick). Engine block is an early 70's with factory heads.
THX -Scott