Speaking from memory since I recently worked on this area - I am sure that Mine was not 6.5" but rather 8". That sound better. PO may have installed incorrect size.

I am thinking the same thing. Mine is 8" too (I own a 2001 MKII). I would think that Catalina would have installed a standard 8", but then again, there have been many inconsistencies over the years...

BTW, if you have a below-the-deck autopilot make certain that there aren't any stray items rattling around down there to disturb the articulating arm. I just had an electronic tech discover that the block of wood that was installed on the underneath side of the sole of the cockpit was detached. That was the reason that it was giving a false read on the rudder location. To prevent that problem again I am planning on installing some kind of basket around that area because I, probably like a lot of people, have loads of odd-shaped items in the hold area of the lazerettes.

Mike, I've read all sorts of "How to drill ss" articles. For this one, though, I suggest you consider having a shop with a drill press do it for you. A few years ago the tongue on my father-in-law's boat trailer broke. We bought new material, but would still be there if it wasn't for his fine machine shop and drill press. Good luck.

Mike perhaps this will explain the difference. My best guess is Foss is making the most recent design which in most cases be OK for use. It appears the rudder post should all be same size according to this pdf. lools like length of exposed post may vary.
This is located in the encyclopedia and under new owner help.

Mike on drilling I had posted this in another post and primarily while drilling you need to use a good drill and pay attention to speed.

[QUOTE=Gary Bain;15910]Michagan Drill is basically the last drill manufacturer here in the US. You can find their website at [url]www.michigandrill.com[/url] they manufacture in Michigan and Florida. They sell drill kits and singular drills. For the most part a Jobbers drill HSS (High speed steel) with 118 degree point general purpose will suffice with care. A drill set with the index 1/16" - 1/2" in 1/32 increments is about $86 list.
Surface footage for SS (Primarily 303, 304, and 316 grades) is approximately 50SFM which equates to feet/minute the following is a guide for you;
1/8" drill= 1528 RPM
1/4" drill= 764 RPM
3/8" drill= 503 RPM
1/2" drill= 382 RPM
So keep in mind as you drill a hole your speed (RPM) needs to go slower as the drill diameter increases. You can increase this speed slightly by going to a colbolt based drill or with some of the newer titanium nitride coated drills. The issue you will have for the most part is the speed of the drill you more than likely will be using, most are fixed.[/QUOTE]

Gary is providing a lot of good info there. A lot of people are afraid is drilling stainless. It is more of a tuffer metal then hard. With stainless you need a lot of lube as well. In my working as a machine repair / machinists I used the rule of a 1 inch drill was 100 rpm. 1/2 inch was 500 rpm ect. That got me by on most metals with out going to my machinists handbook. Good luck.

That my friend is not a drill press but a milling machine. Appears to be a knockoff of a very popular machine referred to as a Bridgeport. I have one in my garage and I have to admit I use it more as a drill press these days. In my early years I made a lot of Die and Mold parts on a Bridgeport when I was an apprentice Tool and Die maker.

Bit of trivia this machine can actually reproduce many of it's parts.

I'm sure it was much easier doing it this way and more than likely the hole alligns with itself from side to side.