Gary this is my proudest moment...after 10yrs studying at dave's university of slightly/maddeningly out of focus photography,i've graduated with honours but seriously...that's a 20mm thick standoff piece of hardwood x 2 plus a 2mm ally cap strips behind the engine mount.It will give you about 2mm clearance between the cowl and spinner backplate.No need to carry any lead unless you run the fa125,then you'll be strapping some to an engine bearer.