Why should I? Personally I think it looks cleaner this way; besides, I was under the impression that we're moving away from drawing the missiles on the rails, due to the difficulty in depicting them in real size configuration. I like and approve of what ace did with the Mk13 launcher. So, in other words, I'm going to keep the rails off missiles.
The Mk 13 was an exception to the rule because of the shear compactness of the launcher and it was stated that is was an exception not the new rule. You've had problems with this before.
While you are at it, please also start labeling your files properly. The proper structure is Pennant#<Space>Ships Name followed by the year if there is more than one drawing.