Okay, here goes: Volvo built a 6-cyl sedan on the 100-series. It was called 164. They also built a 100-series 4-cyl estate wagon, named 145. However, Volvo never built a 100 series 6-cyl estate wagon. They did build a 200-series 6-cyl estate, 265 though. So now a car that was never built by Volvo is for sale: https://worcester.craigslist.org/cto/d/putney-volvo-165-wagon/7084979181.html The 165 is a 164 merged with a 145. Has a longer wheelbase among all features. Restored it will be awesome and well worth doing. This is not the only 165 out there. There is a green one in Sweden as well: https://www.klassiker.nu/bildspel/volvo-165-byggd-av-yngve-nilssons-karosserifabrik
You would think there would be more info and pictures when someone is trying to sell something that unique?