Hard or Easy to Upgrade to Split Phase?

I have an AC300 set up with a 10 circuit Reliance Pro/Tran2 transfer switch. When I first got everything, I was only worried about running my 120V circuits (USA) and not 240V. However with the sale going on, I just picked up another AC300 and B300 for a great price. My single AC300 is running my small home circuits no problem, but I am leaving my AC, oven, water heater, and dryer (all 240V) on grid power. If I now have 2 AC300’s, how feasible is it for me to actually go to split phase now? Do I have to replace the entire transfer switch and L14-30 plug that feeds it? I would love to be able to run my 240V in the event of a power outage. I know I would have to swap some breakers in the transfer switch, but would I have to totally replace it or the plug or the wire?

I have a dual AC300 setup with the Fusion Box Pro and running on Split Phase at 240 VAC for my entire home. But I had a head start by installing a 100 A GE transfer switch behind my main distribution panel in 1995 to use a gasoline generator as I was without utility power due to hurricanes. This came in especially as a lifesaver when Hurricane Maria hit us hard in September 2017 when we lost power for two months. So my AC300 setup substituted my generator in October 2022 with a L14-30 swap, as my home is wired for either one and both my generator and AC300 setup are at the same area. When I was starting with just two B300 batteries, I used the transfer switch often. Now that I have all eight B300 batteries and 3.2 kW of photovoltaic power, my home is on the AC300s all the time (I am on it right now). The only moment I need to transfer back to utility is when I need to use the 30 A clothes dryer a few days a month, since the AC300 is limited to 3 kW or 25 A at 120 V each. I may replace the two AC300s with two AC500s before the end of this year, as they allow 42 A for the 5 kW power output.

In other words, yes, you have to do major changes and rewiring to convert to a full 240 VAC installation. As I posted before, I did the 240 VAC transfer switch installation in 1995. You have to do it now. I wish you success!

Crap lol. Thank you for the insight!!! No worries, I’ll just have a back up incase I ever need it! And I guess in an emergency I could always just move the two units to the dryer or oven and use them directly instead of the transfer switch.