I *hope* you mean, never 'tweak' at all.
The spate of home labs in America is a plague. I have long held and still believe that drug rules should be relaxed to permit doctors to prescribe almost anything to their patients, for the purpose of bona fide treatment of disease, so long as they are held liable for untoward results. No suicide medicine, no tripping just for the sake of tripping.
All hail the oligarchy of doctors!
Legalize and regulate, and home labs will be as rare as moonshine stills.