hoffman style ac30 build which caps?

[menger66]

I'm building a vox ac30 following hoffmans layout, I have a 15 henry choke on hand, the ac30 calls for a 20h choke, will 15h be ok? mark

[pdf64]

It depends on its resistance; my perception is that's the parameter that's more important there anyway, even though the schematic doesn't specify it.
Around 500 ohms with plenty of current handling is good to keep the screen grid dissipation reasonable http://www.bluebellaudio.com/Guitarchok ... DB194E.pdf