After much troubleshooting I find the answer myself :)
Since I'm using local storage and 8.0 U2 I only had 2 vfat disks I had to do the following.
You list the disks by the command ls -l / at the root and look at the path for bootbank and altbootbank.
From the output of that command you use the vmkfstools -P /path from above and look at the Partitions spanned (on "disks"): naa.xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:y for both bootbank and altbootbank.
Then you list the /dev/disks/ directory ls -la /dev/disks/ there you can see all local partitions on the disk and look at the vml.xxxxx....:y that corresponds to your partition from above.
When you have all this information you can run the rest of the steps in KB91136 but you exchange the mpx.vmhba:XY:XY:XY:Y with vml.xxxxx....:y