Don't cut them! Unless a cane is unusually long and will blow around in the wind leave them alone. Tie the climbers up securely so they don't blow in the wind but leave any and all cane length you have. Any of the other roses that seem on the tall side can be staked and tied as well. In the spring when the roses begin to bud out you'll be able to tell how much cane length is winter damaged and needs removal. You will lose some cane length but probably not as much as you think. Particularly if we have as mild a winter as we had last year. If you cut them way down now you're still going to lose some cane and you'll be starting out with much less to work with come spring. Another thing is that those canes have stored energy for next spring so you don't want to cut them off and lose that precious energy. It might be just that little bit that helps bring them back if we do have a severe winter or a very unstable spring thaw. Go ahead and mound the bases like you usually do but just leave the canes alone.