I started to build one, but went with a Vision instead.
Nothing wrong with using a 260 or 290 for a an FE, dunno who told you they wouldn't work??
Anyway, I went with making a full length radio box for all the gear. I sold it to a buddy of mine over here and he has run it with P-Spec power and I was VERY surprised at how well it ran!! If he was a better driver I would have being looking for some more out of my boat that is for sure!
Kris