First off ,if you try to put this magazine on your Yugo SKS you are voiding it's curio and relic status with BATF.Secondly I have tried several large capacity after market magazines on SKS's and most of them are unreliable in feeding or don't stay in the rifle.If you will research messages on several forums you will find others had the same experience.The aftermarket magazines are 98% crap.
Last,I don't understand the need for this much magazine capacity except for the "cool" factor.These long magazines are impossible to shoot from a bench.You are much better off putting the money you would spend on this into ammunition.