Your K2 frame will work fine, everything from your K0 will bolt up to it, as has been said earlier, use your K0 oil tank to mount your right side cover.
As Eric mentioned though, a K0 engine and parts mounted in a K2 frame makes it a "Bitsa" ("Bits of this, and bits of that") so if you can't afford to repair the K0 frame, keep it, and when you sell the bike, tell every prospective customer that you have the correct frame to go with it, and you'll get a lot more money for it. Cheers, Terry.