If you're asking how tall the cuttings need to be, you need to look around a bit more. IMO. The answer is up to you, how hard you wanna trip. Doses and how much mescaline is in cactus is easy info. Generally .5-2% a safe bet, but as low as .3 and high as 5% Who knows?
For an extraction, san pedro is usually preferred over bridgesii, (but bridgesii is awesome monkey fuel too) Usually 1 ft of san pedro will get someone to a light level of tripping. This could vary greatly though, some cuttings are barely more than an inch wide, some are 3.5 and bigger.
You are gonna need to dry the flesh if you plan to use that tek. I have nothing against that tek, haven't tried it yet, but good ol mesc hcl is EZ too + has a history.
Cut up your cuttings, cut out the core, shit there's a great picture tek I think in the cacti section, can't find ATM. You wanna get strips of green flesh dried ideally, then ground that shit, then do your tek. The more mescaline the better, I doubt you will buy too many cuttings. Get 4 or way more feet and start cutting and drying. Have fun.
Edit: whoa, you don't do hcl AND acetate extraction, (unless you mean do both?) see those are both acids, you only need one to get the mescaline. Alternately you can use sulfuric acid. Amount needed will vary.
Read the tek, see the tek, make the tek happen, no variations the first time right?
My ego is insane, but I'm alright
The path of excess leads to the palace of wisdom. -William Blake
Lavos is a fictional character, a dream inside a dream. Don't take what he says to be true or representational of reality in any known form. He is inspired by pure fantasy.