Simul 2:90 re-tube

[daytona123]

I need some advice. I got 4 duet sets of 6L6 tubes for my 2:90. The color codes I received are 2 yellow, 1 red, and 1 grey. Is there a best way to install these? And how are the sets arranged on the amp? This is my 1st retube. (long over due) please help

 

[Roadifier]

The tube patters are set up like this: X__ __ X- inner pair, and another is __XX__- outer pair. This is the way it is on a rectifier, but Im not sure if its the same for a 2:90, but I think it probably is. hope this helps

~zach