and the screen 28 visible to the occupants of the vehicle referring to fig1 18 in another embodiment of a computer 68 the portions that are like those of the computer body 12 u2032 and panel 26 u2032 bear like indicia numbers except that they are primed like the first embodiment the long side 36 u2032 of panel 26 u2032 has notches 45 u2032 forming shoulders 46 u2032 at opposite ends thereof for receiving portions of hinge assemblies 70 and 72 referring further to fig1 15 and 16 in which hinge assembly 70 is representative of both assemblies 70 and 72 the assemblies 70 each have an elongate tubular arm 74 which is rotatably received in an aperture 76 in the shoulder 46 u2032 of panel 26 u2032 oriented perpendicular to the axis of the arm 74 is a downwardly as seen in fig1 extending tubular leg 77 the lower end of which has parallel sides 77 78 shown in fig1 that fit slideably between the sides of a track 86 as best shown in fig1 the upper surface 14 u2032 of the housing of the computer 68 has a pair of parallel tracks 86 88 extending along each side of the keyboard 16 u2032 and each track 86 88 in engaged by the downwardly extending leg 76 of the associated hinge assembly 70 72 as best shown in fig1 the leg 76 of each hinge assembly 70 72 is retained in the associated track 86 88 by a tab 90 at the lower end of the leg 76 also the inner opening 91 of the tubular arm 74 communicates with the opening 92 of the hollow leg 76 for receiving the coiled ribbon 66 of wires.