yeah like dimitri said replace those pucks,use a little hard setting compound on them,while its off remove the points cover and have a go at seeing how the cam timing marks align just for practise,,also the cover goes back on easier in this position,,you should have the valve tappets backed right off before removal as this also makes the install easier,,dont put any pressure on those front four screws in those little "ears",youll snap them off so easy,get the cover mostly squared down then once the cover is close to closing home you can start tightening those ones.