Very difficult to make a tool that will not risk other damage. If you measure carefully the bolt diameter and thread pitch + length, perhaps there is a tool sold for other kits that will fit. I suggest this because most of the IMSB kits use an upgraded center bolt now.
Look carefully at the LN tool kits ?
M96 Faultless Tools IMS Removal & Installation Tool Kit (Req. for 106-08.2.2) LN Engineering
Maybe someone would tell you if this kit fits?
http://www.ebay.com/itm/Porsche-IMS-tool-kit-for-996-986-Boxster-Carrera-/311616982393
Or make an adapter for the tool you already have.
Threaded Mode
