Fluid and filters questions

Hello. I bought a 1999 International 3800 dt466e with AT545. With no damned owner's manual.

Of course, having issues finding a pdf copy online and no one agrees on how much each fluid it will need 🫠

I am replacing all of the fluids and filters to start fresh.

I have 10 gallons of Delvac 1300 Super I bought yesterday after looking at Reddit and various forums. It looks like it'll take 7.5 of these gallons.

I see on forums/Reddit that it has 2 different oil filters.

ETA: WIX shows 51799 for oil filter, 33719, WF10149, 33403 for fuel (surely there can't be three?) 24197, 24206 for coolant No info for transmission filter.

Donaldson's shows: P533235 Air P552071 Coolant P551318 Fuel P550367 Oil No info for transmission filter.

Midwest Bus says https://midwestbusparts.com/product/allison-trans-filter-kit-t112/ is the transmission filter... can anyone confirm?

It's weird that WIX has several and Donaldson's has 1 per... right?