rudder rake adjustment on an 83

Ahh yes, when to ask and when not to? Think I'll ask. I have been doing a lot of reading and adjusting to my boat and a boat I just sold. I started studying the rudders system while tuning a boat to sell. Now i want to fine tune my boat and not sure I can do it w/o buying new parts. I replaced the cams and pins and cross beam to rudder arm doohickies when I bought my boat. Never had any problems.
But then I got to reading about rudder toe in and rake and decided to check out my boat. Not that I think anything is majorly wrong, but maybe I am having to hold the tiller against more pressure than I should. I am no where near the 1 5/8" minimum measurement suggested - more like 3/4". So i see that there is some adjustment available on my lower casting adjustment screws...if only i could turn them. But I can't. They are some size of hex wrench, but none of mine seem to work - 5/32 slips around and 3/16 won't fit in the hole. Do I dare drill them out and get new ones? Is there some other magic to be worked so they can be functional.
Maybe someone stripped the hex hole, but it doesn't look like it. I should mention that I have about 3/8" fore and aft play on one side and about 1/2" on the other. Please set me straight! Thanks, r

That's your problem right there.

Forget about the lower casting hex screws. Cut them off flush with the casting.

Take up the slop with the upper casting adjustment. Problem solved.

Hey thanks Matt! Sounds like the right approach. I will cut off the adjustment screws, but I think some of my slop comes from 28 year old castings and gudgeons as well as 6 year old aluminum rudder pins. I tried to adjust the plates on the upper castings a few times but couldn't seem to get them tight. I'll try some more today. By the way I don't do formal races, even though I do my best to show all the mono hulls on the river who is speed boss. Maybe it's silly to try to tweak my wonderful boat. At my age I hate it when somebody tries to tweak me.

Hey thanks Matt, You must get tired of answering fringe folks' questions over the years. But believe me we appreciate it!
OK, I will cut off the lower casting adjustment screws, but I think a lot of my slop comes from 28 year old gudgeons and castings, as well as 6 year old alum rudder pins. I tried to get the fore and aft play out of the rudders a few times yesterday using the upper casting adjustments, but not much luck. I will try again this morning.

Eureeka! Not sure of spelling. But I decided to dig deeper on the Hobie Forums and discovered Da Dahhhh! Hobie Hotline! Amazing, and with a great article by MattB(with diagrams and pics) on get the slop out! in a column on This Old Hobie! . Had no idea such an info supplying mag existed.
So I printed the article and joined the Association as a sup member. Looking forward to future magazines, though there was an article pushing PFDs which run contrary to my lifestyle.
Hey out there! If you are a new old Hobie owner consider joining. I think it will take a lot of the slop out of the forum! pun intended.