Here's the MQ-1 board mounted behind the ROTJ Hero keyhole (its placement is identical to all the helmets):
[ATTACH=full]173087[/ATTACH]
And the ESB Hero/ROTJ SE helmet:
[ATTACH=full]173095[/ATTACH]
These images shows the inside of the ROTJ helmet:
[ATTACH=full]173088[/ATTACH]
[ATTACH=full]173094[/ATTACH]
And here's the inside of the ESB Hero helmet:
[ATTACH=full]173089[/ATTACH]
[ATTACH=full]173096[/ATTACH]
The MQ-1 board is secured in place with some kind of glue or putty and the lower half is closed with a curved piece (possibly the same material as the visor) which is also secured with the same glue or putty.