A friend of mine told this story last night over dinner:
During his last trip to Lahore, he went with a friend in his Suzuki Mehran to get the roofliner repaired since it was saagging due to failed adhesive.
When the repair guy pulled off the roofliner to add more glue, the inside of the roof was an old Coca Cola sign, complete with logo that had never been painted.That means that the roof itself was not automotive grade steel at all.
I cannot vouch for the accuracy of this story since somebody else narrated it to me, so please do not take this as proven fact.