Yes, that is the right style wheel wrench--luckily, not hard to find these days, a bunch popped up a couple years ago. Other contents of the tool kit;
USAG 252 Vanadium Extra 22/19, 17/14, 17/13, 10/8. The 17/13 and 10/8 are especially hard to find.
USAG 21mm spark plug wrench, most on Mangusta have fixed handle (parts book shows the movable handle as shipped with Ferrari Dino, as in picture above).
Red-handled pliers; probably ~165mm Belzer, remotely Gedore, with semi-translucent 'flared' handles. Very Hard to find the right one.
small screwdriver kit; the bag is impossible to find (!) Not sure the modular screwdriver was shipped for every year, its just possible that later cars came with 2 fixed screwdrivers. Would love to see a later kit.
Brush; ask Denis 
https://pantera.infopop.cc/topic/mangusta-tool-kit