Col
Both sides of the box cross tube clamps were cracked, also I had a job removing the cross tube, had to cut it out, have had the clamps reinstated & laser welded, & re-machined, will be using a stainless tube when I fit it to my 16/80 Special & bonded mounts in the chassis!
Have sent request to Barry Foster for any information he can supply, he did an article on the Morris MG crash box which is similar & somebody else did a cross section drawing, but we will see !