CaptnTJ, Thank you for the consideration, currently the foreguy is deck mounted so I think structurally we can compensate especially if we use a plates under the deck rather than just washers. As far as the jibes, it would be clear of the fore stay regardless. The halyard will be above it so we can jibe by running the sheets in front of the furled headsail (could do "outside" jibes too I guess, but that would be a lot of pulling really fast to get is all the way around before wrapping on itself). The main reason I want to go up is to clear the headstay and do "inside" jibes.
Jackdaw, you are right I'm only racing PHRF not one design. There is at most a handful of this boat on the entire US east coast. Yikes!!! Failure at the hounds conjures up a horrible image of the mast snapping in half forward hitting the water and sweeping aft. If I get that meaning correct.
The halyard restrainer sounds promising. Although I hate the idea adding more holes to the mast. I've been looking around locally, the Club Swan42 runs at the masthead and there are a bunch of J-Boats 105 is in between as you suggest and the 109 and 111 are masthead.
I flew a used J-133 asym for a about 45 seconds as a test in 2.5 knots. It drove the bow down about 18" the clew almost reached the cockpit and we snapped the aluminum whisker pole. But it was massive!
The foreguy fitting on the deck does not carry much load typically when running with a symmetrical chute. So, I'm having a difficult time picturing the relevance of that to the rigging for a gennaker. If you were referring to the forestay, it's load is likely carried by a tang going down the bow of the boat, either externally or internally.
There are several deck mounted sprit options that you can use if you want to go that route. The main purpose of the sprit is to increase "J" and get your sail ahead of the jib, that is create separation between the sails.
Having owned and sailed boats with bow sprits, I'm having a hard time seeing where flying a J133 assy on your boat was a good idea. And, secondly, having a hard time understanding why a whisker pole was used at all. The J133's "J" measurement with sprit extended is significanly longer than your "J" measurement. Thus, using a sail from that boat would give you a sail that is simply too large for your rig. It's no wonder it pushed the bow down. You're lucky you didn't pull your rig down. A properly fitted assy that is properly sailed will pull the bow out of the water some, depending on the boat.
Finally, unless you are grand prix racing, skip the pole when flying a gennaker on your boat. I've flown assymetrical chutes tacked to a spinnaker pole when racing on a boat with both types of spinnakers. It is a hassle to gybe an assy using a pole due to the many control lines, and is beyond the skill level of the average PHRF sailor. Better to use an add on sprit or tack it to the bow.
Finally, how other boats are rigged will not tell you whether your boat can withstand the forces of a mast head chute when it was designed for a frac chute. Each boat is engineered for the sail plan drawn by the architect, and no two boats are the same. The big issue is the stiffness of the mast above the hounds and how well the tip is supported. Do something not very smart and you will have a bit of that mast dangling from up top along with a ruined sail or two.
Good luck!
