Quick-n-dirty walkthrough from the underside.
A HO Victorian house gratings.
B Bulkhead doors from UFO kit, repositioned to be 'racetrack' style magazines for those 12.7 cm missiles. And
these guys think their U-shaped magazine for the AR15 is 'revolutionary'.
C Twin ATGM rails from Hind Mi-24
D 48th scale Grumman Duck rocket rack
E HO T-62 turret race pieces.
F Sprue reinforcements as bulkhead braces. To upper left, sprue as underside/bottom half of flight computer (probably should have beaten it up some more so as not to look so sprue-like)
G Drop down crew ladder from ... Victorian House grating.
Make a note of this, factors into our later monkeying around with the hull.H Great Western sprue, horizontal
I Great Western sprue, verticle
J Maintenance deck for missile arm motor, again the Victorian house grating.
K Lumpy looking missiles. Note that one of them (#3 of 4) has already been expended. Thanks, A10 kit with tons of ordnance.
(was editing while you were posting, elmayerle ). Upper left (white) is the fuze box.
L HO scale T62 turret races attached to Great Western sprue. White is HO fireplug, to the left is HO Victorian house grating.
I figured that since this was a saucer design, circles had something major to do with it's form and function (hence the paddle wheel sprues of smaller-than-turret diameter, in both the horizontal and vertical planes).
Peripheral inspiration