Well, as with the ROTS Vader mask, they made the Jango helmet so it's actually symmetrical in overall dimensions. The severe asymmetry of the Boba helmet is not there. Looks like they averaged out the right and left sides, rather than making one side or the other "correct" and altering the other to match.
Somewhat academic fiddly stuff about the rangefinder area... The Jango r/f doesn't move. The shots where it is seen to are CG -- and the r/f moves in a direction the slot doesn't allow. I roll my eyes at that scene every time. It's like the CG artist interpreted the r/f as a forward-looking camera tied into internal systems, rather than an external display that drops down into the range of vision to show auxiliary sensor data -- as from a missile or starship's sensors. Additionally, where the upper earcap cover is raised on Boba's, it is lowered to be fitted together with the lower earcap on Jango's. I had hoped with the improvement of budget and practical effects, they would have done something to improve upon the mechanism. Say, have the r/f and its block, with the outer cap, raise up about a quarter of an inch to unlock the rotation; then, as the earcap and block continue translating upward the rest of the way, the r/f drops into its deployed position. Worm gears and micromotors could accomplish that with a minimum of engineering. *sigh*
Also, Jango's helmet does have a slight crease running front-to-back, up at the top of the dome and a bit to the left side. It's roughly the same size and in roughly the same position as the gash on the dome of the PrePro 1 Boba helmet. Some people think it is the iconic Boba dent (and that Boba's helmet is Jango's repainted), despite being neither the right size nor right shape nor in the right spot. And the makers of Jango's helmet had a good half-dozen actual Boba helmets in the Archive to use for reference, so I reject that theory right out of hand. Some maintain he gets the ding when the reek tramples him on Geonosis, but it was there before that. Some maintain it's when he hits his head on Slave I's hatch, but it was there before that, too. It's just a like-father-like-son homage.
--Jonah
