This is what I started with. The Arisaka is battle-sighted at 300 meters, which means it shoots insanely high at 100 yards. The idea was to put a long eye relief scope on it so that I could actually hit something with it without resorting to permanent modifications.
Removing the old sight is easily done by driving out the pivot pin with a pin punch and lifting it off.
The spring is held on by a single screw. Removing the screw allows for the removal of the spring.
The spring is removed by driving it forward with a hammer and punch until it comes loose.
The old sight is removed and the scout mount can be installed.
The mount was made for a Type 99 or a Type 38 full length rifle, not for the Type 30 carbine. A new hole had to be machined 18mm behind the old one in order to mount it on the carbine.
The "top hat" nut is inserted, small end first, into the spring mount. It is tapered so it tightens up as it is driven in to the right spot.
Two screws are driven in where the pivot pin was driven out to hold the scope mount
and then a single screw is driven through the new hole into the top hat nut in the spring mount.
An allen screw is used to tighten the mount against the rear mounting screws to make sure nothing moves.
The scope rings come with the mount and are held on with four allen head screws, the screws can be used to adjust the scope left to right for initial alignment.
I wanted to be able to use the stripper clips, so before I tightened the scope down I put a loaded stripper clip in to make sure I had enough clearance. I then put a borescope light in the chamber, pointed it at a convenient wall, and adjusted the scope crosshairs to the light spot.
The next thing to do is take it to the range and zero it in.
UPDATE: 11/23 - I took the rifle to Hunting Partner's house to see if it was close enough to stalk the elusive North American Hoofed Rat and it was still shooting insanely high. We cranked the adjustment down just as far as it would go but it was still 10-12" high. So, the trusty 12 gauge had to do the deed for deer and the Arisaka came back home in the case.
Once home I took the mount back off and took the file to it. There was a ridge halfway between the top hat hole and the rear mounting screw hole that had to come off, then the mount went back on and the scope back atop it. With the scope adjustment set to approximately mid (there are 8 full turns from tight to loose, I tightened the adjustment as tight as I was comfortable with and backed it off 4 full turns) the horizontal crosshair is slightly lower than it was at full tight on the un-modified mount, so I think this is going to work.
Range time next Saturday (and of course I just got the word that there is going to be a CMP Rimfire match that day, too, so I'll
miss that again) so the scope will get dialed in then. After that perhaps we will see if it is a successful hunter, but I'll just be glad if I can actually hit where I'm aiming with it.