Interesting article!!!!
The first Birfield I changed on was a blown one on 4-dice. We did not have a spare so we were just pulling it to go out in 3 WD. It was an original one in the axle and it was stamped "Made in England".
If you take a close look at the joint on an IFS half shaft, they are basically a “Birfield” and I have read a few articles on people using them on a driveshaft instead a CV, and they have held up fine.
