My Europe-spec Abbra came with very little in the way of built-in formers, servo trays &c.
Just one 1/8 thick ?herex/glass/epoxy tray in the fus some way aft of the wing tube.
I installed a long tray extending well forward to carry things like the tank, rx batt etc., made from 1/8/3mm blue foam with 50gm/sq.metre glasscloth epoxied each side. Nyrod plastic tube for the servo screws, little strips of lightply to spread load near tywraps.