[Amps] Plate hardware for Eimac tubes

[Mark Beckwith]

Hi - having some difficulty here swapping tubes around.  Is there a standard 
tool/hardware size for the plate caps and heat sinks on top of the Eimac 
tubes (I'm working with 3-500s and 4-400s this evening trying to get an amp 
working).  It seems like it must be a Torx T5.  Is that right?  Is it 
standard?  Hex keys don't seem to work, and the set screw heads are so small 
I really can't see them well enough to get after it without risking damaging 
tool or part. (Also I don't have a Torx T5 and it just seems like that must 
be it but I don't have one to try).

Help?  Thanks.

73 - Mark N5OT