This is the thickness gauge for rocker arm adjustment, has KING DICK on near side and KING DICK 017 on far side. The feeler leaf will be different thickness for different cars.

.017" hot for MGA 1500 and Magnette
.015" cold for MGA 1600 and 1600-MK-II
.018" hot for MGA Twin Cam (.014-.015 cold)


Click for higher resoluton PDF copy of the drawing. Thanks to Rodney Fisher in Australia for copies of original factory drawings of these tools.