actually I've got a few pictures so you can see what you're in for - it's really pretty simple. Take off front and back covers. Inside the front cover, you'll have to peel the old gasket out of the way - there's a very tiny roll pin that has to be knocked out with a pin punch for everything to come apart.
You can see that tiny roll pin in the first picture - which is a little deceiving, that pivot pin with the knurled ends fits through the arm part with the casting numbers on it - in this picture it looks like one part.
The ONE thing you have to be careful about taking these valves apart is to not lose that roll pin into the valve (like I did on my first try!) If you've got the valve out and on your bench - don't stand it up on end so you can work form the top - instead lay it in its normal position so when the pin drops out, it'l just fall to the bottom of the casting and you can safely fish it out.
The knurled end pivot pin, as you can see, is two parts - they both slide out of the casting one in one direction the other in the other direction.
Then with that pivot pin out and that whole weird looking cage thing, the main valve part can push right out the back. There is one large ring on the back - it has an inner grove that holds the garter spring. (a separate picture so you can see the garter spring).
That valve part can be unscrewed on both ends - there are a few parts inside to clean and that need o-rings. (final picture).
Removing the two "screw cap" type of ends from the valve part can be a little tough - the back end is pretty easy - but the front one, you'll probably need to make a custom tool to get it unscrewed - just basicaly a large flat screwdrive with a notch filled into it to get over that center protrusion (it'll be obvious when you see it).
I used a piece of flat steel stock about 1" x 1/8" thick - and just filed a square notch in the edge. Harder to explain than to do. No pictures of it though.
With that main valve part out - the whole valve body is just basically one big casting. That's all there is to it. Just flush it all out good. (in the last picture you can see the small offset hole where MY roll pin dropped down into... and why I say lay it flat)
Not the greatest pictures, but they should help you see that it's not rocket science - it'll all be easy once you see inside with your own eyes.
The online diagrams makes it easy to fit the parts together properly.