Create SR with retail price for item number

Corrigo has requested that AppTree modify the create SR form we have developed to include the item number and retail price. The following sample work order create with custom fields was provided to us by Corrigo. This indicated that we need to use custom field descriptor ID instead of the custom field name. We are trying to identify the descriptor ID for the custom field "!L_Item #!M_Retail Price" but do not find it in the list. Please refer to the following url for a list of what we are currently seeing. https://www.dropbox.com/s/0xkegb50sole3oe/corrigo_customfieldslist.jpg?dl=0

Please advise how to find the descriptor ID for this custom field, and provide an updated sample work order create request that includes this custom field.

Sample work order create request with custom fields:

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:int="http://corrigo.com/integration/">
<soap:Header>
<int:CorrigoNetOptions>
<int:ImposeConcurrencyId>false</int:ImposeConcurrencyId>
<int:UpdateLastModified>true</int:UpdateLastModified>
<int:CanDeleteMissingEntity>false</int:CanDeleteMissingEntity>
<int:LockOnDataRetrieval>Default</int:LockOnDataRetrieval>
</int:CorrigoNetOptions>
</soap:Header>
<soap:Body>
<int:Execute><int:commandRequest xsi:type="int:WoCreateCommand" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

<int:WorkOrder>
<int:TypeCategory>Request</int:TypeCategory>
<int:SubType>
<int:Id>259</int:Id>
</int:SubType>
<int:Customer>
<int:Id>27</int:Id>
</int:Customer>
<int:ContactName>BL Testing Again 2/18</int:ContactName>
<int:ContactAddress>
<int:AddrTypeId>Contact</int:AddrTypeId>
<int:Address>214-555-1234</int:Address>
</int:ContactAddress>
<int:Items>
<int:WoItem>
<int:Asset> <int:Id>4182</int:Id>
</int:Asset>
<int:Task>
<int:Id>14819</int:Id>
</int:Task>
</int:WoItem>
</int:Items>
<int:CustomFields>
<int:CustomField2>
<int:Descriptor>
<int:Id>1</int:Id>
<!--
<int:ActorTypeId>WO</int:ActorTypeId>

                 <int:Length>256</int:Length>
                 <int:Type>String</int:Type>
                 <int:Name>External WO Number</int:Name>   
                 -->               
              </int:Descriptor>
              <int:ObjectTypeId>WO</int:ObjectTypeId>
              <int:Value>123456</int:Value>
           </int:CustomField2>               
           <int:CustomField2> 
                            
              <int:Descriptor>
              <int:Id>11</int:Id>
                 <int:ActorTypeId>WO</int:ActorTypeId>
                 <int:Length>256</int:Length>
                 <int:Type>String</int:Type>
                 <int:Name>Cost Center</int:Name>                  
              </int:Descriptor>
              <int:ObjectTypeId>WO</int:ObjectTypeId>
              <int:Value>350</int:Value>
           </int:CustomField2>
          
           </int:CustomFields>

</int:WorkOrder>
<int:ComputeSchedule>true</int:ComputeSchedule>
</int:commandRequest></int:Execute>
</soap:Body>
</soap:Envelope>