As far as mg/ml that will depend on your source. I made my own and it's 4mg./ml just b/c that was easiest, and I use a slin needle to dose it.
But most price lists show 4 mg/ml
Also like much bigger said some estrogen is good, so you may only want to run the l-dex when gyno sets in along with some nolva. for a short period of time.
If you are starting off right from the start with the l-dex then test is't really for you if you can't take the sides unless it were a cutting cycle.