OK, I have an ACOG that looks as though it has been drug behind a truck ;)  Still works great, though.  I'm thinking about useing some Krylon on it, nice Coyote-ish color to match my Aim Point.  The ACOG is no beuty queen, she's had multiple touch ups with black paint pen already

Here is the question: holding the fiber optic tube on is a roll pin, can the pin be taken out to remove the fiber optic tube, or should I just mask off the tube with some tape?  

I contacted Trijicon a while back asking about replaceing the tube due to all the cracks, they said not to disassemble it myself, it had to go back... to the price of $280 for the new fiber optic tube which would eventually develop cracks, and they wouldn't refinish the scope because of the labor involved.

i've painted 2....
just tape off the fiber optic and the lenses and go at it....i wouldn't mess with removing the tube, you're likely to do more harm than good....

When I talked to Trijicon about the Fiber Optic tube cracking they said to send it back for a FREE replacement. They even saidthey can replace it with a different make of tube that isnt quite as clear, but does not crack, if I liked.

I know they have a tube made of somethinf differnet since the tubes crack very badly if they come in contact with the main ingerdient in bug repellent sprays.

Quoted: I contacted Trijicon a while back asking about replaceing the tube due to all the cracks, they said not to disassemble it myself, it had to go back... to the price of $280 for the new fiber optic tube which would eventually develop cracks, and they wouldn't refinish the scope because of the labor involved.

Call them again and be clear as to what your asking them to do.  The price you quoted is for a new Trintium replacement, not fiber optic tube.  I know, as I talked to someone there last week about this and was told the current price is $290 for BAC models.  The last I knew, defective tube replacement is free if it has the crack.  

On a side note, my TA31DOC has a clearer tube, and has not show any signs of cracking.