Joining QF10 in PER transferring to QF95, clear customs in PER or MEL?

I'll be flying to the US in May on QF10 from PER to MEL, then QF95 from MEL to LAX. I know it's the same plane, and with the new customs hall open in PER at terminal 4 does anyone know if I can/will clear customs in PER or if I need to do that in MEL?

You'll clear immigration in Perth and once arriving in Melbourne you should be released into the airside terminal area (after another possible security check).

I've done a similar sort of transit back when QF8 flew as Dallas-Brisbane-Sydney, with the Brisbane-Sydney leg via the international terminals.

I began my journey in Brisbane, flying Brisbane-Sydney on QF8 and was continuing onwards on a Sydney-Hong Kong flight - I was checked-in from Brisbane through to Hong Kong and departed Brisbane as an 'international' passenger (so no orange D sticker), and just went through transit security screening in Sydney without going out and back through passport control.

While technically there'd be no requirement to go through security again at the Australian transit point, that'd only be possible if the 'upward' aerobridge is unlocked so that you can enter the airside area, which in my case it wasn't.

On other 'domestic international' transits, such as from Brisbane to Hong Kong via Cairns, I've just been able to walk up into the departures hall without going through security again.

Thanks for the replies, I'll update after my trip in May