Protank heads can be a bit fiddly to re coil, but not overly difficult. The easiest 'first attempt' build is, imo, a nice and tight little microcoil, and assemble with the drill bit, tiny screwdriver, or whatever else you use to wind around, left through the coil. That way, the job of lining up the coil neatly in line with the slots, avoiding shorts, and getting the right tension on 'the legs' is just about done for you. Just a matter of putting a bit of cotton wool ball through, and jobs a good 'un.
Personally, I dislike cotton in a protank, but the microcoil/cotton combo was definitely the easiest way for me when I cut my teeth on rebuilding the Ptanks.
Once you get to grips, it's worth experimenting with coil diameters and/or leg lengths because once you find that 'perfect size' that just manages to avoid touching the push in chimney post, you can forget flavour wicks (and even the chimney post grommet if you feel brave) and enjoy protank no flooding, no gurgling, no leaking, super flavour, super cloud heaven.
Enjoy the fun