this picture is from my latest mod.
if you look at the cartridge, it is a custom one I made from a cut dse103 cartridge and a a dse901 cartridge.
the dse103 part allows for it to fit 103 atomizers, and the 901 cartridge holds more e-liquid.
i havent tried it yet, but I imagine you can use it on a 103 as well.
just take a knife and cut through the 103 cartridge. make sure you measure the length well so the 901 cartridge, when fitted in, will touch the wick of the atomizer on your 103.
fit the 103 cartridge on your atomizer, backwards. this may be a little tight and hard to fit in.
then, slip your 901 cartridge onto the open end of the 103 cartridge that has been cut. you will find that it fits perfectly!
this will, however, require you to buy 901 cartridges. my 2 cents.