Driveshaft Interchange 7.5 versus 8.8 rear end

[demonswede]

What is the difference between these two Mark VII driveshafts or do they interchange?
My driveshaft for 7.5 rear end is getting worse but I do have a 8.8 rear end driveshaft. Can I swap these?

[84mark]

haven't heard of any diff. in the driveshaft relative to the rear

[demonswede]

U-joints are the same. Could the 8.8 be shorter? Or could the bolt ring to rear end be wider? According to Hollander, the driveshafts are not the same (part nos).