Under dash heater box studs that go through firewall on for 67-72 C10

[HeavyHauler]

I am getting ready to remove the under dash heater box on my 68 C10 which did not come from the factory with AC.

There are some studs on that box that stick through the firewall which help mount the heater core box to the firewall.

One stud is not in very good condition. Can these studs be removed from the underdash heater box?

I could chase the threads but I am just wondering if I could replace them both instead.