Well worthwhile.

Whilst the headliner is out and you've solved your sunroof leaks, if you live in a really hot area/state a good tip is to install some hi performance alu foil coated thin insulation (20mm thick) above the headliner, this stops radiated heat into your cab. Be careful though where you have exposed electrical connectors as both sides are alu sheeting and liable to cause a short circuit or fire. Use heat shrink electrical insulation on these connectors before installing the main alu foil insulation.