1.5 is probably a safe bet.I do the same, I use 2-3 different spots on my lats
Highly underrated site. Can take at least 1.5ml no problem for me, haven't been willing to go higher than that, but I'm sure I could
I recently did 2.7ML without any pip or problems, didn't leak from the muscle either, but it's probably better to do 1.5 and spread it around for better absorption