1) Ive heard that rumor too, but it personally does not seem possible to me because the 54r chevrons are spaced out quite abit, and the POSP/PO/PSO's tend to be single focal plane scopes (so its not like you can adjust the zoom to make it match up)... I believe the 54r reticle chevrons are to be used only after your elevation dial (marked in meter's) has been maxed out; then the chevrons equate to 1100, 1200, 1300 and so forth. I doubt there is any compatibility between the ballistics but have yet to try it.
2) Id stick to the SVD style side plates ( A rail that has a groove/void up the middle, and some sort of stopper piece machined into the barrel end of the plate) , They work with POSP/PO/PSO's that have SVD or Universal style Clamps on the bottom.
An SVD style side plate like this
(this one may require machining out the metal in the groove to allow some scope stoppers to slide down the middle)
or this
or the one i used for my SKS
(I notice the stopper on the barrel end is missing in the picture for some reason)
With these mounts, you could most likely utilize every style of POSP/PO/PSO available in Canada, But i would be wary about weather or not the POSPs with AK style clamps (the clamps that elevate the scopes higher) would attach properly. I wouldnt use them anyways because they are designed for the very tall receivers of AK platform rifles, in result they appear to sit ridiculously high on every Red rifle in Canada (ive never owned this style, but ive seen pictures of them). An SVD side plate bolted to your SKS at the right level on the receiver will be able to equip both 24 and 42mm obj scopes, and keep your irons free, but there will be that fine line where the 42 will sit just right, but then the 24 will look slightly high. Having the 24 sit low and getting an AK style elevated clamp 42 that works with the SVD side plate may work out, but it could also result in the 42 sitting to high Idk. Id match the side mount so the 42 sits just at a barely tolerable height, which should make a 24 sit alright. Getting complicated there. Keep in mind the scopes hang out to the left far enough that it is hard for them to actually obstruct your irons anyways, if mounted low enough, the Obj lens will hit the left corner of your SKS's rear leaf sight before it will obstruct the view.
4) Depends on what you use your SKS for, Mine i use for coyote hunting 1-300yrds, I like to identify targets and sweep the scenery long distances away so i enjoy having all the magnification i can get. If i take the gun into the bush, i just slip the POSP off into my pack and use the irons, or if im scoping and a rabbit runs out from the bush underneath me, i'll press tight on my cheek weld and use the irons with the POSP still attached. I plan on using my SKS for 3-gun or run and gun competitions in the years to come, so I may buy a PK-A red dot for that just because i hate using the SKS's irons.
The world of details behind the POSP/PO/PSO's is a confusing one, with many different opinions and very little sound information to go off of. This is just my interpretation of what ive come to learn from collecting up a pool of opinions and what ive come across researching, buying and mounting the 3 side mount scopes that i currently own.
That SKS is really set up to be a good, rugged, grocery getter and coyote gun. High speed mag changes aren't really a big deal for that.
