Yes, you can use the 'Custom Property Editor' application on your primary polling server to add custom fields to your node properties. If these do not show up in your current node details view, you may have to edit your current view to include the 'custom properties' web resource in your current node details view.
If what you are looking for is to add it directly to the Nodes Details resource, you can easily edit the 01-NodeDetails.Resource in the Inetpub/Solarwinds/Netperfmon/Resources directory. Just add a table row with the appropriate property like so:
<td class="Property" width="10"> </td>
<td class="PropertyHeader">Serial Number</td>
<td class="Property"> </td>
<td class="Property"><a <%=Node.GetProperty("ParamString")%> href="/NetPerfMon/View.asp?View=NodeDetails&NetObject=N:<%=Node.NodeID%>"><%=Node.GetProperty("Serial_Number")%></a></td>
I've done this for some interface details. If you do go this route, you will want to create a copy of the original resource, make changes to the copy, and replace the resource on the website with your modified version. The reason for this is because whenever you do a re-install, the installer will overwrite your hard work with the default page and you have to do it all over again.