Ouch, sorry to hear that :( . If there is any possible way to pull it out for repair I would strongly suggest that option. The odds are that if you hit something hard enough to make the rudder inoperable it likely did some damage to the rudder shell. And as you said trying to straighten and true...
You are just evacuating the air in the shaft log so water can get to the seal. Otherwise you may have a airlock inside the log which will stop ANY water getting up to seal. I don't think a flatter hull mitigates the need of burping the seal IMHO.
If the bellows are new you may need a tool to break that seal. A putty knife(carefully) worked well for me. To check compression you would have to loosen the collar and reset, which means replacing the set screws as they are single use according to PSS. Compression on a 1" shaft is 3/4". If it's...
You don't mention any vibration so "Squeaky" sound leads me to the dripless. Burp/flush it good to be sure there isn't any debris stuck on the surfaces. Do you know if the dripless is getting HOT to the touch ? If so it's not getting water flow.
Think it's the shelf for the reefer compressor ? I would think it's hollow but may have structural elements inside. Not much usable space in there. May want to build something on top maybe ?
Water does get into the mast & is unavoidable. Make sure the drain hole at the base of the mast is clear and allowing water to escape. It's a very small rectangular slot, aft end. The other culprit is the wiring and how it is routed through the deck. It helps if the wiring in the mast has a...
Which Raymarine instruments do you have ? I had my Garmin plotter at the helm and when I finally took the effort to wire in the instruments through NMEA 2k I really loved I could get all that info on it. You would be surprised at how much more info and calculations are available once it's all...
I have to say I am a bucket and brush guy. I have only used a power washer below the water line. A 5 gallon bucket with Dawn dish soap(sometimes a little vinegar for slimy areas), extendable handle brush and swab the decks ! Smaller brush is handy for getting under tracks and nooks and crannies.
Just disconnect the "in and "out" hoses and join them together with a fitting and clamps from the hardware. I would get a straight and a 90 degree fitting in hand before you pull the hoses. You also may have to release a hose bracket or 2 to get enough slack to join them together. Probably 3/4"...