Series 3 Series 3 Propshaft Lengths - How Critical?

Got my S3 88" propshafts down off the shelf at the weekend to clean them up and install new UJs, ready to go back on the vehicle at build time.
Turns out that they are both the same length. Now the book says that the front one should be about 50 mm longer than the rear on a shortie like mine.
These shafts came off a working vehicle, so it all definitely went together at one stage. Admittedly two of the UJs are toast, but the others are both OK. What I'd like to understand is what are my options here to put them back in. If I reinstall the shafts I have, ie put a short one on to the front diff, where a slightly longer one should be, presumably it is only an issue at full front droop? Alternatively I can get myself a new or second hand front propshaft. Does anyone else out there run two short propshafts front and rear?

Thanks in advance.
Andrew

I think when I fitted mine they were both the same . Works OK for me

When I did mine one of them was way too long and the other too short.

Took me ages to sort it.

Thanks guys - I think I have a source for a second hand front one, so I'll see if I can get one there.

Cheers
Andrew