Figure~??[f.frm] shows the possible frames and the applicable ;SPMlt;modifier;SPMgt;s with reference to the notes below.
3
: Allow ;SPMlt;frame variant;SPMgt;s like those used for directionals, , |2<#210#>-<#210#>| should be the same as |<#211#>=<#211#>|. Add |<#212#>o,<#212#>| and more brackets.