I would suggest you replace both it if you can them out. Chase the internal threads and then install the new grade 8 studs coated with neverseize.
Coat the threads for the flange also before you install the nuts. It will save you a lot of headaches 20 years from now when you rebuild it again.

Don

1967 GMC 9500 Fire Ladder Truck
"The Flag Pole"
In the Stovebolt Gallery
1946 2-Ton grain truck
1946 3/4-ton pickup,
1953 1-ton pickup
1957 1-ton flatbed dually,
1954 Pontiac Straight Eight
Of all the things I've lost in my life, I miss my mind the most!