it depends on your compression. If its hic, you just need a long enough shim, if its a tilt scs and they were legacys, I dont think you need any. If you did, it'd be either a 2 or 5mm. As for other scs' you'd need at least a 5 or maybe both the 2 and 5. As for the deck lengths, I honestly found it easier do do whip tricks on a longer deck, because it gives me more room to move around, but they both feel much better than a reventon imo.