This is a pretty straight forward project, but it does require some mechanical ability as well as some tools.
This sight will work without modifying the front sight other than adjusting for elevation.
Ideally, a mig or tig welder would be best for ruggedness and speed of completion, but this can be done completely and turn out as well with only a hacksaw, drill and tap using button head screws.
Parts and material list:
3/4" square steel tubing commonly available from hardware stores.
AR-15 A2 aperture
AR-15 A2 rear aperture leaf spring.
AR-15 A2 windage screw.
AR-15 A1 or A2 windage drum.
5/32" or 1/8" x 3/4" roll pin for front sight spring retainer.
Optional would be the small roll pin to pin the drum on, but a small nail or brad that fits snug works as well.
Also its a choice of the style of windage drum, I built the 1st one with the A2 knob, and it blocks some vision I felt, next one I used the plate type. No need for windage detent assembly, the tension from the leaf spring keeps the screw from turning freely.
You start by cutting a length of square tubing to a rough length. Its easier to drill the holes before you cut out the top or shape it.
Next step is drilling the holes for the windage screw and is pretty crucial for function. It really helps to have a drill press for this to make it easier to keep straight in both axis. Drill through both sides with a 5/32 bit. You have some margin for screw placement relative to the bottom, but not much. From .210 to .240 is about most range you have to deal with. Any less and the aperture will bottom out and will not flip up, any more and the spring will not hold enough tension to keep it solid against the stop and stay vertical and/or jiggle.
Now is the time to decide which side the windage drum will be on. The windage screw has a shoulder on the slotted head sideopposite of the drum, you will have to open the hole out for it to sit flush. A 13/64 bit is very close and still undersized, I went through with it and finished with a round file. You can also adjust for minor misalignment of holes with a file as you open it. You can wait to finish the holes until you remove the top side of the tubing, but its much easier to hold straight in a vice if the tube is intact while finishing the holes.
Once the holes are done, remove the top side of the square tubing leaving the sides as high as possible. The shape is up to your imagination and taste. I wanted to continue the line going up from the back of the receiver cover for looks, but you can move the position of the aperture back more if you shape it differently.
Now is the time to clean up, remove burrs and smooth edges etc, before putting the parts in.
Test fit all the parts now to ensure the aperture moves etc. The hole for the pin in the windage screw works out to be just about right for the 3/4" tubing, if it has a gap, I would suggest going to an auto parts store and getting the thin shim washers and putting behind the drum to tighten it up.
Next is probably the most tedious part of the whole thing, making retainers for the leaf spring.
I welded in plates beveled to hold the spring in, they could be left loose and attached with the screws used to attach the sight to the cover, its just makes getting it all aligned to drill the holes and mounted more tedious. Remember the aperture leaf also uses these as a stop to stay vertical, so you would have to mind the height of the screw protrusion. A flat edge on the plate would probably work to keep the spring in place, but I didn't want to chance the spring jiggling and working its way out. If you do it right, the flat spring is always under some tension, so if you drilled the holes at the right height, it won't be able to move past the plates.
The type of cover needs to be the heavier smooth style, I would not recommend trying to put one of these on a ribbed cover. All mine have been built on Chinese covers I picked up on an auction, but Saiga covers are at least as heavy and would work fine. Also receiver cover fit is important for this to work well. It has to be tight
, all the way against the slot in front, and contacting the rear side of the slot in the rear trunnion. You can bend the cover slightly to fit more snuggly in the rear, and change the radius of curve up front slight to keep it from moving there also. But its important that its very snug to the point its hard to take off.
You need to remove the the original AK sight, but leave the leaf spring in and use the 5/32"x3/4" roll pin through the hole to hold it. The front sight will most likely have to be raised some in elevation to match the rear but it should require no modification.
Finish with your choice. I have used allumahyde II and cold blue over sand blasted frame both with decent results.
Anyone capable of building kit or even converting a Saiga can do one of these without risking a brain aneurysm or investing in a roll of ducttape to wrap your head in.
Some pics of the finished one showing mounting and close up.