The Tapco T6 (tactical) stock you're referring to is an excellent, sturdy piece. Very simple swap.
Keep in mind 922(r) compliance. You'll have to win the "10 or less imported parts" game...
Which generally means USA made stock and handguard (T6 stock covers this)
New USA stamped magazines (tapco has great ones) which count as three compliance parts (mag body, follower, floorplate)
The Yugo will need the grenade launcher removed, and either the threads cut off or a USA muzzle brake permanantly attached (ricks muzzle brakes)
As well as a USA made operating rod and gas piston (tapco also carries)
This brings the total number of imported parts to sec. 922(r) compliance.
If you need more info, do a search over on the sksboards.com forums. PLenty of info there.
Also, call tapco's help line...they can help as well.