I have a few pairs of Garbo alloy dampers that will fit more or less directly onto the PB Racing Dart. The original PB springs can be used but I have some progressively wound items that match the dampers.
The spring adjusting collars even have the same thread, so can be used with these dampers.
The shock absorbers will fit front or rear with very little work and I may test them when the weather and time permit.
To view a bigger version click on th image.
Update: I have since fitted different shock absorbers to the Dart and these articles are listed under the Dart Modifications section.
PB Dart Modifications