Well I've been dabbling in the same thing the last few months.
My recommendation if you want top sound quality is a Sansui professional series from the late 70's
AU11000, AU20000,AU30000. recapped these are as good or better then pretty much anything below $6k in a modern amp. and they have way more features then modern amps generally do. well no DAC-streaming of course.
very attractive looking love the rose sides, tops and black face but all the knobs are silver, and very well built.
https://audio-database.com/SANSUI/amp/au-20000-e.html
I've started a build on the professional series separates CA 2000 and BA ???? (anyone have an amp they want to part with).