C30 front axle weight capacity?

[6 Door King]

Looking to find out the overall weight rating for the front axle on an 82 C-30. I want to use the independent suspension setup from a donor truck in the rear of another truck as a bogey or tandem axle and I am curious just how much weight it could offset. My guess is somewhere north 3500 pounds since it was responsible for supporting half the original truck and a ton of payload. I know that weight distribution plays a role in just how much weight would have been on the front axle versus the rear, but if I recall properly the empty truck weight is about 6k. Any help would be appreciated.