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Advice on building S-100 IDE board V2 (74H04 vs 74HCT04?)

Hi everyone!
Today I got some old scrap boards/circuits and recovered enough components to build an IDE V2 card (one of those with the single IDE connector on them).
I've completed my build, except for a component which is leaving me some doubts: U4 is a 74LS04 on the silkscreen, but on the card's page (http://s100computers.com/My%20System%20Pages/IDE%20Board/My%20IDE%20Card.htm) it's written that it MUST be a 74S04 or 74H04.
On the V3 card description there it's mentioned that this component was required because the outputs reached a level high enough for the IDE specs, a level which was not attained with LS ICs. AFAIK both 74S and 74H are still TTL chips, wouldn't it make sense to replace the '04 with a 74HCT04 which surely reaches a level high enough to satisfy the requirements?
Ideas? Opinions?

I'm considering just trying and see what happens, but it'll take some time before I'm able to write 6502 code capable of using the IDE board.