Distributor ignition amplifier bolt size?

[Top Gear TVR]

Slightly stumped but what size bolt is it that holds the ignition amplifier to the distributor body on a 2.9 v6 cologne.

Sod all that i have will read, 5.5mm long reach doesn't get it?

[phillpot]

Had to modify a socket.......

5.5mm / 7/32" / 5BA

[Top Gear TVR]

i have long thin shakers but still no joy.... grinder it is then! or chisel, or axe?

[Top Gear TVR]

Phillpot special does it! Now to see if it's cured the problem