Making the cut

[Joel143]

I have this Trichocereus Magrogonus "BIG MAC". I apologize if the pic is not a good one. The pic is of the cactus before it got to me. But as you see where the main trunk was cut and is callused over. When it rains and/or when it is watered, water tends to puddle in this area. The main stem at times is alittle soft...not firm like it should be. I would like to remove the two pups that are growing and start them on their own. I could then place the main plant in the greenhouse for further pups and keep it out of the rain. My question is where to cut to remove the two pups? I have read to take some of the main trunk along with the pup in order to root it. Is this true? In the past with other cactus I've just either twisted or cut just below where the pups are attached. Would this be the same case.

Any info would be greatly appreciated. Thanks in advance for any info given.

[modern.shaman]

You don't need the main stem for it to root. You can do what you have done with the other cacti just remove them and let them callous
I would cut just above the join (leave a little on the main stem) so you have a even flat cut but it doesn't make a difference.
Once they callous just pot them up and give them about a month before watering so they have roots and don't rot.