67-72 vs. 73-87 crossmember

[68blazer]

Hello all, i have been lurking around this site for years doing homework and studing all sorts of different topics. I have had a 1968 SWB in my back yard for years and i've recently disassembled it and i'm currently doing a frame off. I also bought a 1975 Long bed for the front cross member / disc brakes and suspension. i've heard that using the newer front end has greater benefits, does anyone know for sure?
here is the pic of the stud from the 75 cross member.

it was so rusted and wore down i cut if off and started to drill it out. i have spent way too much time trying to drill it out. here is the pic of the punch stuck in the crossmember stud hole, any other ideas?



for arguements sake i still have the one from the 68 and as far as i can tell all the measurements of the crossmember itself are the same. The Studs look a heck of a lot better on the 68 then the 75, obviously i'm not talking about using the upper and lower control arms, but in this next pic i put the newer upper control arm rod from the 75 on the studs of the 68 to see if they fit.
if you have stayed with me this far, Thank You! and hopefully you can answer my question. what would be the good/bad/ugly of putting the 75 suspension on a 68 crossmember??
here is a pic of both years together

any info or opinions or comments will be appreciated