Clip together construction. There are three projections inside the body sides each side which engage in the chassis. Carefully pull the body side outwards to disengage, then ease the body up. Be careful not to scratch the paint off the body side, a fairly blunt instrument like a thumbnaill is preferable to metal; that also means you won't go too far up inside and dislodge the glazing. (The good news is that on all the examples I have had the glazing is easily freed, great if planning on flush glazing, which much improves the look of these vehicles.) Also when reassembling be sure to get the interior right way round relative to the exterior, there is no 'fits only one way round' protection to prevent this happening.