The original Rutherford Engineering kit as fitted to Woodstock use a new lower spring plate as the wheel end shock absorber mount. Plenty of metal there and I'd be very surprised if anyone has ever broken one.
The factory one is dreadful and I can see the stresses that will have lead to this problem. Apart from using a very superior metal for the plate, no real answer and from a design/engineering point of view, dreadful on several scores.
