Do you mean draw one first then the other in the same syringe? if so it would not matter which you drew first. it is not the order you draw it that causes it to crystalize. it is when the two compunds mix. i have never used trenbolone so I have no clue but I know a lot of bros on here use it and have never heard them complain of it.
If your worried about it then run a little test. Do about .2cc of each in the same syringe so you dont waste much gear. If it crystalizes then dont mix them.