How do I get 90% max fire res now?

Seems like since I last played infernoclasp is no longer droppable (+5 / +6)?
Kitava ascendency no longer has +5 max fire res on the armour.

I want a talisman build (so no rise of the phoenix)

Theres only a couple max elemental res on the passive tree, and maybe two more from a glove socketable.
ruby gems can roll +1 max fire res.
purity of fire doesn't give max fire res in poe2.

Where can I get the rest from? Do I need giants blood to wield the talisman and use rise of the phoenix?

Giant Blood doesn't work with Talisman.

So the most I can get is +4 to max fire res? +1 per jewel slot?

Against the Darkness Unique Jewel can roll +1% max fire res for each notable passive in radius. It can give you 3 to 5% depending of your skill tree.

glove 2 socket with 100% increased socket effect = 4%
darkness enthroned belt 2 socket 100% increased socket effect = 4%
rise of phoenix shield = 5%
sunsplinter shield = 1-3%
corrupted amulet + body armour 1% per = 2% max all ele
corrupted belt = 1-3%
ruby jewel = 1% per
heart of the well unique jewel = 1%
against the darkness = 1% per notable

Winner. Thank you sir!

Just picked up a 2 max fire res darkness enthroned 72 % gloves for 1 chaos. I think that's probably the best I'll be able to do in the belt slot without multi divs.