It's completely possible, but it requires the fairly unique (in this community) combination of patience and responsibility.

Get a full subincision so that your urethra healing over doesn't pose a risk. Then spend literally months making gradual cuts at the base of your cock, waiting for it to heal enough to be manageable in between cutting sessions. Then, finally, spend an evening with a tube of xylocaine cream and finish the job.

Given the blood-stain that I just woke up on top of, I'm not 100% sure that I'm not going to end up going to the ER, but the bleeding seems manageable enough when I'm awake, and a scab is forming pretty fast, so I'm going to let things ride for a day or two before I make any rash decisions.

There is a video of a guy finishing his self done removal. He first split his cock and slowly removed each half. The video showed him removing the last half completing the penectomy. Claims he healed in 21 days. He goes by Dickless1964 there and Lovemoddedmen here.

Yep, you are referring to me sir