Yes part of the radio mast assembly is hidden in this photo, although assuming the later replacement Vospers had the more advanced SO radar fitted, and that their assembly was similar to those shown in jonco's photos of MTB 670
, which seem quite chunky and relatively low set, then I imagine it would still be visible.
The information I have passed on comes from a small pamphlet, A History of the 24th MTB Flotilla
, written by H.F. Cooper, whose details I understand were incorporated into Mediterranean MTBs at War
, co-authored with Len Reynolds. From reading the pamphlet, it does seem as though the bulk of the activities involving commandoes and partisans, took place during an operational time frame that spanned their deployment with the Special Service Flotilla, until their eventual paying off, and that the removal of torpedo tubes took place at the beginning of this period, thereby making MTBs 81
, and 242
, reasonably strong candidates for the boat in question. The other boats of the 24th Flotilla had 20mm Breda guns fitted for additional armament.
Possible locations range from Komiza, on the island of Vis, through to Brindisi, Manfredonia, Ancona, and in particular Bari, where regular exercises apparently took place in which commandos practised launching and re-embarking their collapsible boats.