It's a 4 stage process:

- 15Nm
- 35Nm
- 90 degrees
- wait 10 min then another 90 degrees

The second 90-degrees will make sounds like a submarnie imploding in the Marianas Trench.

Bolt sequence:

<-- front ---------- rear -->

24 - 20 - 16 - 12 - 08 - 04 - 02 - 06 - 10 - 14 - 18 - 22 - 26

23 - 19 - 15 - 11 - 07 - 03 - 01 - 05 - 09 - 13 - 17 - 21 - 25

Don't forget the two internal hex head bolts into the timing chain cover and the two by the fuel filter block.

There's a specified loosening sequence for the cam bearings and a strict warning that you will bend or break the cam if you don't obey. The cam bearings hide some of the head bolts so the cam has to come off.

Sixto
95 S420
87 300SDL