50/50 or 100/100 dual mono block: tube tray

[D-Max]

Question: anybody with a Marshall EL34 50/50 or 100/100 rack amp willing to measure and share the depth (or height) of the grey tube tray?

The Marshall 9100 and 9200 monoblock rack amps came with the shorter type of 5881 power tubes.
Thus Marshall made a tube tray just deep enough: 11mm (7/16 inch)



Later on Marshall were getting a good supply of EL34's again and they updated the mono block rack amps by increasing the depth of the tube tray to accommodate the taller EL34's.
These updated rack amps were labelled EL34 50/50 and 100/100.

I am looking for the depth of the tube tray of the Marshall EL34 50/50 or 100/100 tube tray:

 

[Jon Snell]

17" x 13" x 5 1/2" with 5881s so add a little for EL34s.
Should fit nicely in a 4U 19" case, with cooling fans.

 

[D-Max]

For clarification: the question is about the grey tube tray in the middle of the chassis of the amp, which has the octal sockets for 4 or 8 power tubes.