Sub ActivateAngleConstraint()
  Dim doc As Document
  Set doc = ThisApplication.ActiveDocument
  If (doc Is Nothing) Then Exit Sub
  If (doc.DocumentType <> kAssemblyDocumentObject) Then Exit Sub
  
  Dim assemDoc As AssemblyDocument
  Set assemDoc = doc
  Dim compDef As AssemblyComponentDefinition
  Set compDef = assemDoc.ComponentDefinition
  
  Dim params As Parameters
  Set params = compDef.Parameters
  
  params.Item("d350").Expression = "90 deg"
  
  Dim constraints As AssemblyConstraints
  Set constraints = compDef.constraints
  
  constraints.Item("Angle:1").Suppressed = False
  
  assemDoc.Update
End Sub