Try recalibrating your pedal position sensor.https://www.crownvic.net/ubbthreads/ubbthreads.php?ubb=showflat&Number=4019500
A proper tune (especially one from Marty Ochs of MO's Speed Shop) will eliminate almost all of the lag.
Further reductions can be attained by swapping in a larger throttle body.
Trying to revert to a cable throttle would cause more issues and be more work than provide any benefit. There's a reason no one has actually done it, though many people have looked into it (and ultimately decided against it).
Member of Northwest Panthers Car Club
2008 P71, Norsea Blue SAP
-Message Center cluster retrofit
-Towncar Signature L heated power seats
-Long overhead console
-Compustar remote start/security