fluid storage tank mounted near the rear end of the truck bed 13 and having a top bracket 12a mounting a hinge pin 14 at the top of the pedestal a steel tube 16 has a pair of hinge plates 17 mounted to its sides adjacent each of the two bottom corners of it and which form a yoke straddling the pedestal top 12a and pinned to it by the pin 14 whereby the tube can be pivoted about the axis of pin 14 from a generally horizontal transport position as shown in fig1 to the vertical drilling position shown by the dotted outline 16a in fig1 this pivoting action is powered by a double acting single rod end hydraulic lifting cylinder 18 pinned to the pedestal at 19 and having piston rod pinned to the hinge plates at 21 a hydraulic pull down cylinder 22 is locate in the tube 16 it is a double acting cylinder having heads at both ends each of which is bolted to the sides of the tube by a pair of bolts in each side cylinder head 23a is bolted adjacent the rear end of the tube 16 the piston rod end head 23b is bolted to.