Hi First to declair an interest I have a Six for sale. With 3 rigs. Yes you can only have one Mast so its best to get a Groovy mast each Jid can have its own boom. I have Down loaded the Frank Russell plans not sure about them I thinkif I was going to build my first Six I would look at Graham Bantocks "Rococo" I am currently rebuilding a Wood "Rococo" and have just finished fitting out a Carbon "Rococo" for a club member, its worth buying a set of plans form Graham just to look at them and always remember there are lot of "Roicoco" owners out there who will share info with you Regards JohnK