Ederd,
The bolts can fail if the correct spacers are not installed properly.
Here is a good picture of parts needed (944online).
Pelican can get the bolt & spacers or you can possibly machine/improvise. Refer to a PET for part numbers.
You need to be careful or you could ruin the PS mount --Lower balance shaft.
One other thing, there is an upgraded hose and fitting (item 7 in pic) for the reservoir to PS pump. Shorter. Pelican.
GL
John