Ha! Re-designing the transformers is most of the tricky work. Yes; you will have to do that.
It might require some experimentation. Try to use FT-61 hog-nose material. I think it will be more
or less good for this application. FT-43 might work, but it will taper off at higher frequencies.
Keep the layout rather simple and try, if possible, to make it on a separate board with inputs and
outputs as far away from each other as possible. Some feedback mechanism between drain
and gate (or drain and ground) may be necessary. Simple attenuation impedance or transformer
matches should work for driving the gates, since the capacitance is quite low. Keep in mind the
WA2EBY layout and matching -- that should be a good guide.
I was thinking of setting the two output MOSFETS with 2N3866 drivers. Should put out about 10-14W
from 80m to 10m, with a drive of .5W or so...maybe less.