There are websites which telling you how to do all sorts of things. This doesn't mean it's recommended. I apologise for trying to help:
"36. Should I take my test apart to see the line(s) more clearly? No. Removing the test from its plastic case changes the test's exposure to air and humidity. Air and humidity affect the manner and rate at which the dye and chemicals cross the test. If you change the environment before the test is finished, you risk drying it out too quickly and when a test dries too quickly, the dye may dry in places it would not have otherwise making an evap line appear to be a positive result. Additionally, the tests are intended to be used and read while intact. If you think you see a line, but it is so faint you really can't tell, it's probably an evap line and should be considered negative.
Please note: pregnancy tests will work almost anywhere-- the problem is not the amount of air or humidity in general, but changing it in the middle. HPT's are scientific little things, and to achieve greatest accuracy, the environment should not be changed while the test is running.
If you want to photograph or scan your test for posterity (or for posting to your message board buddies for opinions ;) it can be easier when removed from its plastic casing (to eliminate glare.) If your test is positive, go for it! If it's negative, or you're not sure, you're in a tough spot . . . removing the test from its casing while the test is still wet can "speed-dry" an evap line and make it darker/harder to interpret. But tests are not completely dry at the 10-minute time limit; by the time they dry, the test has passed the 10-minute limit and should not be read. If you think you'll be in conundrum, use a dip-style test or remove the test from its casing before you apply urine. "
www.peeonastick.com/hptfaq.html#36"
Every test I've ever used that is inside a case specifically said in the instructions not to dismantle. I'm sorry my advice wasn't what you wanted.