Asalam o Alaikum!
Dude the problem you are telling is abt the "Gatri", its the front mart of the mehran, near the front thiya. As the mehran is not meant for these roads you should take care,specially new mehrans are of worst quality.Well i had a similar problem, my GATRI also got rusted, the Gatri is fixed by nuts and bolts, but my mehrans GATRI had to be changed from the points where the nuts and bolts have to be fixed, so i had to install a new one, but instead of doing dat i got it weld. But as your car is 2005 i will recommend you to change the GATRI with a new one, will cost you around 1500Rs. Including installation.
Hope that may help you.