MGBs were produced with a castor angle of 6.5 degrees to allow for tyre slip of 10 to 11 degrees. Modern tyres have a slip angle of 2 to 3 degrees, causing the MGB steering to load up and become increasingly heavy the harder you corner.
Received the wedges that i bought on eBay this morning. They are used but not the type of thing that wears out. I think this is a project for later in the year.
More about the caster correction wedges at …… http://www.frontlinedevelopments.com/part/castor-correction-kit/
Another independant review of these caster correction wedges found here at …. https://www.mgcarclubdc.com/techtips/castor.html