Yes the lense can be removed easy enough, however the needle requires a spechial tool to remove it without bending the internal workings.
Even with the correct tools, every altimeter that has had physical loads applyed to the internal workings, (pulling off the needle and putting it back on), should be checked in a test chamber to insure that you have not dammaged the workings or affected the calabration in any way.
Jumping the altimeter without testing it in controled conditions is NOT recomended. And NO, a jump is not a controled condition.
I am stressing this because of the potenchial danger that an altimeter that is not working correctly can present. At the very least, one of wich is a two canopies out, after the Cypres fired when the user pulled to low because their altimeter stuck or was out of calibration.
Alti-2 is at a lot of boogies buring the year. They have a chamber that they test altimeters for calibration for free. They will not be happy that you have altered their model of altimeter, but that aside they should run it up so you can see if it is with in speck and is working smooth throuht the entire range.
To everyone, there is no reason to risk safety. Be carefull up there, the planet will not move out of the way for you! Sorey.