Well, with two parts plus water, there are at least 3 things to screw up, and 3 factorial (6)possible outcomes only one of which is the desired one.
With regard to high viscosity, I have found that the Chemistry Store, which is about the cheapest place to get a gallon of TEA, also sells containers including Boston rounds of various sizes and lotion pumps to fit. The lotion pump is the best way I have found to move small quantities of gooey stuff from the container to a graduated cylinder. Each stroke of the pump moves about 1/2 ml. You don't have to use the full stroke. I see they are out of stock in white pumps but have others. Another place to look is www.sks-bottle.com.