Two of the same prune types are much easier to deal with as far as prunning goes, but if I do have one of each together I just prune the 2's as 3's and go on. All I'm doing is delaying the bloom time of the 2's for a little while. Sandy

Sandy's right about trying to keep the same pruning types together..ut's just easier...but I am a naughty planter and mix them up but have learned who is what and I hard prune the three's and then several days later can see the dying vines and pull them out leaving my two's alone..Two's are only pruned after blooming and only to shape and keep in bounds...Jeanne

Is it too late to prune my clematis

No, it is not too late.