Unfortunately you have not made any reference to a picture. That would have been a help.
But take a look here:
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Photo © Normando Carvalho Jr.
I guess part of the mechanism for adjusting the horizontal stabilizer is located in front of the stabilizer (inside the fuselage).
If you take a closer look at the 777 and the 747 then this area seems smaller than on the A320 and the 737. Since the big planes have a bigger fuselage then there is (almost) enough room inside the tail cone for the mechanism.
On the smaller planes the tail cone has a bigger dent above and below the stabilizer to create enough space inside the cone for the mechanism. The reflection above the stabilizer (starting at the windows) on the A320 clearly illustrates this dent.
Part of the reason for this big surface could be the need for smoothness to reduce aerodynamical resistance from the tail.
Yours in realtime
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