Converting to a traditional cable setup from an electronic throttle body would be much more hassle than it is worth. You have to remember, apart from pointless government regulations, the shift to electronic throttle control also eliminated the need for a separate IAC valve and cruise control module. It probably cut production costs to some extent as well, which I would imagine, was the main drive behind it.
At a bare minimum, apart from a new throttle body and TPS, you would also have to replace the intake plenum with one from a older vehicle. Then you'd have the joy of replacing the gas pedal (and maybe the entire pedal assembly if you have adjustable pedals), fishing the throttle cables (which may or may not require drilling), and of course a good bit of rewiring. If you can't modify your existing zip tube to accommodate the IAC, you may need to replace that as well. If you want functioning cruise control, not only would you need to install a module, but you'd have to rewire the entire system and probably go as far as replacing the clock spring in the steering column, and perhaps even the steering wheel if you cannot get the '05+ controls to work.
Simplest way forward, and the cheapest, will be the tune option from Marty.
Lucifer: '01 Grand Marquis GS ConvenienceTuned By Marty @ Mo's Speed ShopIn Memory of Ned Nuss, Rick Richardson and Matt (2vmodular)