Yes I have it.

What you need is a bigger trannies to be able to take the load, different rectifier tube (GZ34) and a bigger chatode resistor (10W).



big PT


 

I actually had 6L6 in my 5E3 from day one, so I actually don't know how my 5E3 sounds with 6V6.
You can hear how it sounds in a "5E3 Tweed Deluxe SoundClips" thread. I have a clip there.
I like it very much but you should also know I installed a vol/tone mod from Mission amps.

 

Before anyone reads this and tries it, running a 5U4 in a 5E3 without a significantly larger PT is a recipe for disaster.  It is true that Neil runs 6L6's in his Deluxe, but I doubt he runs a 5U4 (maybe a 5AR4/GZ34 or a 5V4).  The 5U4 draws 3 amps of current and most be used with a PT designed to supply that much current on it's 5 volt tap (by comparison the 5AR4/GZ34, 5V4 and 5Y3 draw 2 amps).

The danger with running 6L6GC's in place of 6V6's is they they draw twice as much current (2x6L6GC draws 2.8A, 2x6V6GT draws 1.4A).  Many people run 6L6GC's with a traditional Tweed Deluxe PT and have no problem, but a good recommendation is to replace the rectifier with a Weber Copper Cap and free up the 2A that the 5Y3 was drawing, this will relieve any stress on the PT. Of course, you'll still have a mismatch of impedance between the OT and speaker (switching to 6L6GC's will make the optimum secondary impedance 4 ohms and an OT that is too small to benefit from the 6L6GC's extra output.

Mcinku did it right and built the amp to run the 6L6GC's optimally.  But, the 6V6GT is more like a lower powered EL34 than a lower-powered 6L6GC, switching to a 6L6GC will remove some of the creaminess and Tweed Deluxe distortion character, but result in a bigger, more balanced tone.  Making it a little more like an under-powered Tweed Bassman than a over-powered Tweed Deluxe.