[murphyv310]

Contrary to the belief that the layout is ultra critical I can say without a shadow of doubt it's not.

Be sensible with the layout. My stereo 3-3 uses two busbars, one HT the other ground and returned to chassis at one single point. Its hum free and bang on spec, it works beautifully with any combination of EF86/EL84 even Russian valves. I also have a 3-3 test amp that only has 250v HT although it's only just over 2 Watts the distortion level is only marginally raised and sounds excellent, they are actually less effected by low HT than some think. I've made many 3-3s now and for a single ended amp are brilliant, knocking spots off those two grand triode amps with 300B valves. I did a comparison last year with the stereo 3-3 and a 300B amp with a HiFi dealer and he came away shaking his head after the comparison. He even asked me to go into production and make some, which I declined.
Why not try an EF37A & EL34 3-3?