Here are a few notes I've combined from various sources re this design of Vosper, might be helpful when picking an option for your completed models.
Built from the box the Italeri kit represents a Vosper built 72' 6" boat in the range 73 to 98.
*NB: Boat 73, the first of the batch appears to have been built with an earlier style of 'bridge' bullet-deflector, the front was more rounded than subsequent boats. Later images of 73 seem to show that the square deflector was retro-fitted at some point.
MTB74 was modified with relocated 18" torpedo tubes and changes to superstructure and camouflage scheme to support the St. Nazaire raid in 1942, it was sunk during the operation.
MTBs 73, 75, 76, 77, 78, 79, 82, 84 and 95 were sent to Malta in 1942 as the 8th MTB Flotilla but were incorporated into the 7th Flotilla on arrival.
- source Reynolds & Cooper - Mediterranean MTBs At War.
Boats in the range 222 to 245 were built by Vospers and a number of sub-contractors but all appear to have been identical in outward appearance.
- source Lambert & Brown - Allied Torpedo Boats.
246 to 257 were built by White under contract and were again nominally identical to the Italeri kit.
- source Lambert & Brown - Allied Torpedo Boats.
258 to 316 - US built, typical identification features being no scuttles (portholes), lack of 'Vosper' trim fittings around the engine exhausts and increasingly heavier weapons, single Oerlikon on the forecastle and a twin Oerlikon in place of the twin Vickers Mk.V turret.
- source Lambert & Brown - Allied Torpedo Boats.
Boats in the range 347 to 362 were all but identical to the earlier Vospers except for a triple rudder arrangement, one for each prop, again heavier weapons were fitted to this series particularly the twin .50 Vickers Mk.V turret was replaced by a twin 20mm Oerlikon mount.
- source Lambert & Brown - Allied Torpedo Boats.
363 to 378 - US built by the Annapolis Yacht Yard, see above.
- source Lambert & Brown - Allied Torpedo Boats.
396 to 411 - US built by Jacob in Bay City, see above.
- source Lambert & Brown - Allied Torpedo Boats.
Of course this only applies to the the boats 'as built', in the field each boat would have been modified, repaired and upgraded, pictures exist of MTBs 77, 84 and 250 fitted with a captured Italian 20mm Breda cannon on the forecastle.
Some boats carried grenade launchers or pintle mounted Lewis .303 or Vickers GO guns on top of the torpedo tubes.
Ballistic padding was often wrapped around the wheelhouse and bridge and of course on later boats the wheelhouse was stripped of controls and the windows permenantly blacked-out so it became a charthouse.
Of course all the radar and IFF fits were constantly being modified and updated as the war prgressed.
Alas I've discovered that the boat I really wanted to do, MTB86, was fitted with a single 20mm Oerlikon forward, not a Breda, which is a shame as I really like the camouflage scheme on that one.
HTH