You should try and postpone the U/A for at least 3 days. Because anytime you utilize dilution techniques, you need to do some creatine-loading and allow those 3 days for the body to metabolize the creatine into creatinine. Creatinine is the end waste product thats found in urine and tested by the labs to determine an overdiluted sample. Failure to load up on creatine, or not allowing the time necessary for metabolization will greatly increase the chance of the urine sample to be ruled "too-dilute".

Skip the aspirin because its old tech. Back in the day, it was used as an interferant for only one type of test: the first-generation EMIT screen. Since then, a second-gen EMIT (aka EMIT II) was introduced to counter the interference issues caused by aspirin. As a result, the first-gen EMIT is seldom used anymore (if, at all).

Drinking fluids is only helpful on the day of the U/A. Drinking fluids days before the test is of no help. The dilution phenomena is only temporary. Once all of the fluids ingested had all been urinated out, the "dirty" donor will resume testing positive for THC.