is generally indicated at 44 and comprises a frame 46 consisting of a number of steel elements welded together the frame 46 includes a lower bridge 48 and an upper bridge 50 which at their ends are attached to a pair of drill guides 52 which are of a cylindrical tubular configuration the lower end of the drill guides 52 are affixed to rectangular end portions 54 and each of the end portions 54 includes a lower surface upon which a partially spherical projection 56 is formed as appreciated from fig4 the projections 56 each include a spherical surface 58 which is identical in size to the anchor base recess 34 in this manner the projections 56 are capable of being closely received within the recesses 34 a vertically adjustable retainer 60 is mounted upon each of the end portions 54 and each retainer consists of a threaded shaft 62 received within a threaded hole defined in the associated end portion 54 each threaded shaft 62 includes a hexagonal rim 63 and a head 64 is defined upon the upper end of the shaft for engagement with the machine a to be supported as later described preferably a self aligning ball and socket connection is located between the shaft 62 and head 64 so that if during use a misalignment occurs between the axes of the shaft 62 and head 64 such misalignment will be automatically compensated the angular orientation of the drill fixture 44 during use is determined by the threaded angle adjustment shaft 66 received within a threaded hole defined in.