Ah, but I've already booted my working large board on the bench with the broken unit's smaller board (it reprogrammed my unit to Territory profile). Had no issues booting though
In fact, the small-board, LCD-backlight, LCD-screen & touch-screen units I'm currently using are all from known good units... The 2nd SAT NAV unit I bought (as a spare) had a small scratch on the touch-screen - so I put the worst part on this unit (knowing it's never going back in a car). This broken unit had a really nice touch-screen panel, once cleaned with LCD cleaner solution.