I just got through doing this on my 86 X. 3 hours start to finish, and that was taking my time and scratching my head a bit, removing and disassembling the pedal, fixing the pedal, welding the pedal, putting out the small fire, taking the dog for a walk, etc.
Tools needed - 7mm wrench for acces plug, 13mm for ebrake cover and cable bracket at cam box. 10mm socket and extension if you are going to remove the pedal. philips screwdriver to get the console out, 8mm wrench to remove the back end from the old throttle cable. flat screwdriver to pop off the old e-clip, and needle nose pliers to remove the old cotter pins.
I had no need to remove either seat or the steering wheel. I did pull the console back though. Removing the baffle in the firewall was almost impossible. I chose to cut the old cable in half for easier removal. I inserted the new cable from the spare tire compartment out into the engine bay, then fed the nose of the cable into the tube under the e-brake.
Only trouble I had when removing was the the clip securing the accelerator cable in the back of the tunnel. It is about 5" behind the ebrake opening, reach deep and you can easily pop out the accel cable.
For reassemly at the pedal - well that was a bit of a hassle. On the later accelerator pedal, you can use a shortcut that saves needing two people to reassemble :
On the new pedal end of the cable, feed on the grommet/boot and work it into place, then a cotter pin, then through the yoke of the pedal. Slide on the spring and plastic insert, and pull the cable end up until it wont go any further (back binds on the yoke). Now you can push down on the insert/spring and since the end is bound, it will not flop around or pull back. If you are quick and patient, you can tag the final cotter pin in the hole with the spring pulled on in this manner. It is a little tough- your arms will be in front of you and you wont be able to see anything- so familiarize yourself with where the hole is before you scrunch that spring on and go groping for it!
And when you remove the clip that holds the throttle cable to the tube under the e-brake, keep your eyes on it!! That bugger goes flying!
From the glass lined tanks of old Bertone