Hi,
There are 2 different ways to achieve this. First of all you should define an attribute on your bookmap that the authors set to define the desired output type (Service, Technical). You could use the standard DITA attribute "outputclass" on the bookmap element for example. Based on this attribute's value you could do
Approach 1:
When doing "Save As Server Object" you need to map this attribute to a Windchill attribute on your Dynamic Document. You can then use this Windchill attribute in the Publishing Rules to tell PE to use a different stylesheet.
Approach 2:
You handle the outputclass attribute value in your stylesheet. That means you merge the stylesheets into one and define your layout based on the value of the outputclass attribute on the bookmap.
Approach 1 is probably easier to handle as it keeps your stylesheets separate and easier to maintain.
A variant of this would be to define 2 publishing rules for manual publishing from Windchill where you can select the desired output type. If this is working depends on whether you want to do a manual or automatic publishing in Windchill. If you are only doing manual publishing from Windchill that would probably be the easiest way and would not even require the attribute on the bookmap.
To point your publishing rules to use a different stylesheet you need to add this worker parameter to your ruleset (using the standard dita stylesheet as an example here):
<worker name="stylesheet">D:\ptc\PE\custom\doctypes\ditabase\ditabase.style</worker>
Please note that the path to the stylesheet must be an absolute path to the stylesheet file on the Publishing Engine server.
I hope this helps.
Sirko