If you made an extreme change in voltage rating, say using 200-400 or more volt caps where they were originally spec'd for 50V, you may have some inductance issues except I doubt an amp this well endowed doesn't even have more local decoupling, it's unlikely the change to a higher rating like 63WV would be anything but a positive change. Distortion is not a factor here. Resistance does not increase, ESR goes down with higher voltage (in same line of caps, we pretty much have to compare apples:apples).
You cannot just substitute Cerafines, they are significantly lower capacitance density and simply will not fit, unless you are willing to give up a lot of capacitance, and it might not be all that bad since 160,000 uF is quite a lot unless it's the entirety of the PSU, no regulation stage.
With 16 caps you will have quite low ESR already, the primary factor may be what space is available, and given it's likey to run warm, that they're still rated for 105C.
You might consider something like Panasonic TS series, here's Digikey's PDF
for them, see also the cross-reference to other brands at the top for other ideas. You'll have to wade through it to see what'll fit dimension wise, I would stay with at least 63WV rating or 80V, dropping capacitance a little if necessary to make them fit (sometimes, better caps are a larger physical size for the same temp, voltage and capacitance rating).