Hi Dan,
Well done in getting yourself an SD2.
I take it the fuze unscrews ok?....the fact that there was no pics of the fuze removed when this one was for sale had me a little 'concerned' !!
As regards the fitting of the SD2B fuzes (bayonet fitting) these had little metal clips that were fitted to the lugs of the fuze. When inserted into the bomb body they were then locked into place by bending down the outer lug of the clip into a recess on the bomb body.
These clips when attatched to the fuze are an extremely tight fit and most will not turn into position in the bomb casing. I presume they were mean't to be so tight so as not to twist undone during use. However this makes them almost impossible in most cases to clip into the correct position, unless you either flatten the dimples on the clip itself, or have a very worn relic body that has been filed out. Personally I tend to remove the clips from the fuzes and have them fitted in loosley in the correct position. I like to be able to remove them easily without force. The other alternative is just to twist the fuze in slightly with the clips still in place, but this way the fuze is out of correct allignment.
There are a number of posts on the SD2's if you look under 'submunitions' showing the different types.
kind regards
Kev