Marc - i replied to your FB question on this topic with a Honda 6.5kw unit that I'm using. It has been converted to run on petrol or propane by me. Conversion kits are common on the 'net. I'm doing the same thing you're suggesting, a Tee from the main tank into the house for generator. This is going into a 220 volt 50amp breaker into the service panel and I have to go to the street power pole that feeds my house and turn off the 200 amp breaker from the power company so that I don't back feed into the power lines. I don't have a transfer switch to do this automatically but given that I've never had to do this in the 14 years of living here, I'm not too worried about it. My main concern was to run the well pump in case of an extended power outage. I could also take the generator down to the well house and set it up permanently down there on a concrete pad and a tiny house but that has yet to happen. That's really where the generator needs to live, at the power pole so that my house can be fed by PNM or by a Honda

Unfortunately, the propane tank is by the house, which 300' from the power pole.
I do, however, use a tiny honda 2000eu unit to power up the house and selected circuits. This feeds the kitchen fridge, lights and bedroom lights. So far, I've had to do this twice when someone ran into a pole or something and we had an extended outage. My kitchen stove is on propane so cooking is easy during a power outage.