There are several companies that convert gas carbs to e85 carbs but never seen anyone offer to convert a thermoquad to e85. I have seen some Eddy carb now being converted...
It takes more then just increasing the jet size...the internal passages have to be enlarged also, that is why an holley is so simple to convert cause the metering block can be swapped out.
use google and see if anyone is doing them....about all I can say