interface 54 and the female recess 106 males steps 108 may provide for the proper axial and radial alignment of the first stage singlet 122 during installation the first stage singlet 122 then may be fixed into place between the horizontal extension 21 and the outer rings 20 by using the low heat input type weld 109 at the downstream edge of the female recess 106 males steps 108 interface and the low heat input type weld 59 at male female interface 54 in the manner described above alternatively though not illustrated in alternative embodiment the attachment systems of the inner sidewall 44 and outer sidewall 46 as depicted in fig6 may be interchanged accordingly the interface between the outer sidewall 46 and the outer ring 20 may have the female recess 106 male steps 108 as described previously for the inner sidewall 44 and the interface between the inner band 44 and the horizontal extension 21 may have the radial male female interface 54 as described previously for the outer sidewall 46 in such an embodiment except for taking into account the switching of the attachment systems the assembly may proceed as described above referring now to fig7 there is illustrated an alternative embodiment to the present invention a first stage nozzle assembly 150 that utilizes a first stage singlet 152 at the outer sidewall 46 this embodiment demonstrates how the current concepts also may be used with band ring construction which may include a solid band or ring 156 fitted within an outer carrier ring 157 band ring construction may include an interface between the.