So made some great strides in finding info on the ADL stats and dimensions.
Turns out its actually really easy to find them online through google so..... guess im dumb for not trying it earlier
Anywho! Heres what I've found so far:
The basic ADL was consists of 4 long sections (13cm long by 4cm high, or 5-3/16 long by 1-9/16 high for you mericans) and 4 small sections (5cm by 4 cm, or 1-15/16 by 1-9/16). Theres a pic down below of the wall sections (pic 1). Couldnt find a proper top view of them, but you get the idea of the staggered look of the wall. Pretty sure its not too important if they're straight or staggered. This guy made a pretty good one from foam (pic 2).
The actual gun part is just a simple weapon mounted on what looks like just a squard base (pic 3). Not too sure of the dimensions for this guy, but I'm sure just a small square plateform (probably around the size of a small marine base, if not alittle bigger) would work out. I got a whole box of random IG bits and whatnot, so I'll see what I can wipe together.
I'll post my first attempts at the wall later.