An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced, the source spot requiring alignment along a transmission axis passing through the sample spot. A first housing section is provided, to which the x-ray tube is attached, including mounting features for adjustably mounting the x-ray tube therein such that the source spot coincides with the transmission axis. A second housing section includes a second axis coinciding with the transmission axis; and at least one x-ray optic attached to the second housing section for receiving the diverging x-ray beam and directing the beam toward the sample spot. Complimentary mating surfaces may be provided to align the first and second sections, and the optics, to the transmission axis. A third housing section may also be provided, including an aperture through which the x-ray beam passes, and to which a detector may be attached.