I am changing the input gear from my broken 87 231 (21 spl) into my spare 98 231 (23spl) to make the 98 231 a 21 spline input. I noticed the 87 has a stamped steel range fork and the 98 has a cast aluminum one. I have searched to see if one range fork is more desirable than the other, but have not found any info. My personal opinion would be to use the steel fork over the aluminum one. Is one fork better than the other or are they even interchangeable?