I am pretty sure EVERY Lexus has the compartment for the filter,some earlier ones did not have it installed but most all did.
I know in the later 90 models it is usually easier to find behind the glovebox for access as my 98 LS is. On my 94 ES it is behind the carpet beside the gas pedal ,a real pain to get to .
I also used an expensive custom filter material costing $30 ( i can make 2 for this price) instead of the Lexus type filter. It works great but is not a tiny particle filtration as the oem on .