Thor ta-1000 pre cap replacement -- advice

I am a new owner of a Thor TA-1000 preamp. What a fantastic piece of equipment. In my system it has a bit of a hard, tinny treble... just a bit. I want to try replacing caps with something warmer and wondered which caps should i replace? I see two small Hovland Musicaps and two small Multicaps. Then "beneath" the board (looking from the bottom of the unit here).... there are four big black caps... Solens i think. Which caps might be the place to start in order to warm the treble?

Before anyone asks, yes i am certain the treble issue stems from the thor. I have played w cables and tubes and will continue to do so but it needs something a bit more dramatic. I am willing to lose some detail to get rid of the issue.

Rest of system: sota star sapphire, grado reference sonata1, cec transport, audio note 3.1 sig dac, vtl mb-185 sig monoblocks, quad esl-63, vandersteen 2wq subs.

Thanks for thoughts!
Correction... the big caps below the board are actually the electrolytics and I think they are Panasonic. So I'm focused on the Hovlands and Multicaps. Does anyone know which ones are the output caps?
I had all of my TA-1000 capacitors replaced with Vcaps.  Expensive but definitely worth it.  Be forewarned that they will require something like 200 hours of use before they sound their best.  I can send photos if you can figure out how to get your email address to me.

I replaced two more caps, beyond the coupling caps with audio note mylar copper caps. Still breaking in and making tube and cable changes too so I may never be able to.attribute changes to the caps. But things are heading a good direction. Thanks for the input.
augwest - what sonic changes did the capacitor change bring to the T-1000? I’m an original owner T-1000 (upgraded to MkII by Paul Marks) and wondering what my options are for possible sonic improvements.
Sorry your response ended up in my Gmail "promotions" folder. I thought the cap change to audionotes was all upside. I hoped to get rid of some hardness in the treble and it did. But it also added more body and dimension across the spectrum, and I feel like I heard more resolution in the treble bit less. More listenable and less fatiguing, but no loss of information. If anything, the opposite. More organic.

Capacitors can be like delusional attorneys! Projecting importance with relative obscurity!