Originally, I installed the hoist for a 26 foot Century (about 5500#) loaded. At the time, the hoist was rated for 10,000 pounds. When I bought the Grady, it was time to go over it. Fully loaded, the 283 is probably about 9500#. The only thing I changed were the spool pipes and the cables. I upgraded from 1/4 inch SS cables to 5/16 inch. Don't remember the spool pipe but put in the biggest I could fit inside the beam. The motors (2 of them) are 1/2 hp 220 volt. The guy that did my work told me this would increase the capacity to 15,000 pounds. The cables and spool pipes are the limiting factor, not the motors. All else, including the 8-inch diameter wood pilings and structural steel remained the same. The galvanized I-beams are 8 inch, 12 feet long and the bunks are 2/8's ( 2 together on each side). The bunks are 24 inches apart in the front and about 28 inches in the back.
This hoist was a standard design by a local Florida installer. It lifts the boat just fine. The only thing I've had to do to it is keep it lubricated and change the drive belts. I'll change the cables about every 5 years. The hoist is 10 years old and the beams are rusting but should last quite a few more years. I see no reason why this design wouldn't carry a bigger boat. Hope this helps.
JJB