Thanks Jeff. I have new swaybar end bushings (donuts) from MWB. I also have new the round shouldered hard plastic bushing that sits inside the round sway bar control arm mount. However, it seems that with the larger wagon 22mm sway bar may not fit through that hard bushing which does look correct for the thinner 19mm sedan sway bar. I can see how the donuts could stretch over the thicker wagon sway bar.
The modified solution referenced above is to delete the shouldered hard plastic center bushing, and modify the Pirelli Ritmo bushings to fit. Those come with metal sleeves internally that are certainly much smaller than 22mm ID. I will press those out, and see if I need to enlarge the bushing centers to fit over the sway bar to capture the control arm. Or, revert to the stock new donuts. Not sure about the original wagon / control bar bushing configuration. Upon disassembly, a fine crumbly dust emerged which could have been a completely decomposed center ring, or simply accumulated dirt. One of the donuts that came off has a hard plastic backing, but not all of the four donuts.
The wagon swaybar center mounts as far as I could tell stock Fiat bushings unavailable. I ended up sourcing an equivalent from eBay which are originally 22mm for Honda Civic. Will report back as to if those fit. Other alternatives from sources like bushing.com were expensive and most often poly, which I did not want to use, preferring quieter more compliant rubber.
It was also interesting to observe the struts that came off the car were old Boge, and apparently already had stock sedan 7 coil front springs mounted, along with Moog camber adjusters. I have another pair in waiting sourced from MWB which are also 7 spring allegedly from a 128 coupe. Will compare both sets in length once disassembled in length and spring diameter. The car was sitting slightly high in front, as the PO had already performed the lowering block mod trick on the rear. As this is a '74 it originally had the super heavy US bumpers which are long gone. So which springs and if I cut a coil is TBD.