Ranger Mods

Hi everyone,
Does anyone have experience with heavy loads on the roof with off-road driving?
I have to install a heavy tent on the roof (approximately 70 kg).
Given that according to the use and maintenance manual, the Ranger's roof can hold 80 kg.
It is preferable to install two crossbars with a capacity of 100kg on the existing longitudinal bars and respect the maximum load foreseen by Ford, or it is advisable to remove the longitudinal bars and install a Front Runner roof rack weighing 25-30 kg. In this case the support surface is more solid but the maximum load on the roof is exceeded by 15-20 kg.
Has anyone seen any damage with similar loads?

Thanks bye.

For Europe, I think either option would work.
For Australia and dealing with hours of corrugations, I'd use a solution that spreads the load out more evenly into the roof, despite some extra weight.

Thanks