@buellrider97 Hi Mike, you might ask if they ran them in for 2-3 days already before shipping out as some do. You might let them play for at least the first week [or two or three] before changing any tubes, let the caps [if new] settle in, and keep checking for noise and get a solid baseline. Take notes if you can on sound of low, mid, high frequency and what you hear for your own refer-back reference later on.
I'm a dork and pretty conservative about this first phase, maybe even letting the amps play 2-3 weeks as-is before messing with anything at all. Check bias now and every few days if you can as tubes and bits inside settle in. This way you'll know they are still solid and still dead quiet as you stated. I think of it letting everything to simply stabilize to a baseline with added confidence about the "upgrade" itself.
Then, maybe a few weeks down the road, when you start changing any tubes, or start hearing any new noises, you can isolate it a bit easier if by chance a new tube with problems/noise gets introduced. If so, swap the original tubes back in to confirm. Why do i suggest this - here is why.
I recall a few times for different amp owners where "recently upgraded" amps and preamps were shipped right back to the factory for them to test and find out the recently changed-in tubes were the culprit, not the upgrade itself. If it were me, I'd just let 'em play 3 weeks on/off. See how it goes for ya. At that point, you'll know what's going on, and how solid the upgrade is. And then can introduce changes, and will easily notice problems if any changes, tubes, bias, causes new issues.
This approach can also give you an etched-in-the-brain baseline about how it sounds after the upgrade, and then how it sounds again once you change in the new tubes you want to try. People have different approaches, this is mine fwiw.