Trays require a wider rail. That requires a wider boat, so likely that would be the biggest obstacle to a tray on the Revo. How about a Hog Trough? You could mount to the rail?
There is a rod adapter for the sail / accessory mounts. The fitting (Wedge Mount) is for Ram ball use though.
I have two revolution 13's and one is fully rigged for fishing and the other my wife did not want any rod holders added to it. I use the RAM wedge mount when I fish with a buddy. I put the wedge mount with a rod holder in the sail mast hole and works perfectly.http://www.rammount.com/CatalogResults/ ... fault.aspx
As far as measuring I use the Frabill bump board. It floats and I leash behind my seat. It stashes behind the seat nicely and just take it out when needed. Measure in your lap.http://www.basspro.com/Frabill-Bump-Boa ... 61/?cmCat=