Having looked at the cartridges I have I feel it would be way too finicky to take them apart (and I would likely damage them in any ham-fisted attempt).

I personally feel the key will be maximising the mg per ml ratio by avoiding any addition of flavourings or thickeners (VG) and of course using nicotine free PG as the only dilutent. I figure I need to work out how much PG is spent during a decent couple of vapes, then aim to get a decent dose diluted per that amount (I hope to find out a way to vape at least 20 mg with maximum of four hits).

I should be cool to order some in the next 2 weeks once I get end of the month and the usual bills out of the way