In case you think these stress lines are due to a twisting motion on the chassis here are the preferred jacking points, I always use these when servicing etc prior to putting axle stands in place.

http://www.gomog.com/allmorgan/jackpoints2.html


2009 4/4 Sport Henrietta
1999 Indigo Blue +8
2009 4/4 Sport Green prev
1993 Con Green +8 prev