Crisp sounding tubes for Modwright 5400ES

I recently upgraded from a Modwright 9100ES to a Modwright 5400ES. While there were improvements, the richer mid-range and more powerful bottom end of the 5400ES tipped my previously balanced sounding system into one sounding a bit overly polite with a lack if crispness in the top end.
Can anyone advise me on what tubes (output & rectifier) and power cables to chose so as to brighten the top-end.
Grateful for your advise.
Solentgreen, I had the same issue with the Sony. I sold it and bought the modright modded Oppo 95. I like this much better. In my opinion it is more open and extended on top and much tighter in the bass. I tried a lot of tubes with the Sony and ultimately was much happier with the Oppo.
Thanks to all of you for your advise. One thing I neglected to say was that I had already switched to using a Mullard 5AR4 and Sylvania 6sn7 GTBs; sorry for that.
I had read elsewhere in Audiogon forums that the Mullard can be a bit 'overly-sweet' sounding, which I take to be overly-rich? So I was looking initially to change the rectifier tube for something which would give a crisper top-end. I read in another forum that the EML 5U4G has a more more open top end. Has anyone tried this?
Jwn, thanks for the benefit of your experience with the Oppo. I did think about this but then stopped when I read the following thread, where their observation was the the Oppo was fuller and warmer sounding. I am sure your experience was valid in your system; I guess that's the thing with our hobby; there are so many combinations and permutations and different outcomes in audio.
If your goal is to add more crispness on the top, then I would go with Audience Powerchord for the power cables. I have this pc on all my components now. I would also recommend the Sophias for the output tubes. The Sophias are not euphonic or "tubey" sounding. They are instead linear and 3D. I have the Modwright tube Oppo 83, which I thought was a tad too warm when I first got it. The Audience powerchords and Sophia tubes brought the sound of my rig back into balance.

What are you using for ic's and speaker cables?
I would contact audiogon user Fork on the Create audio 5AR4. I got mine from him. It is not unusual to have to wait. Limited supply and
I hear a lot of people really like this tube. Based on my experience I think it might be a better choice for you. I found the vintage Mullard wonderful, but almost too much of a good thing in the Modwright sony.