Easy.
Bits you need (off the top of my head from when I did it to a pre-facelift 5-6 years ago)
Manual box plus cross-member.
Flywheel
Clutch
Clutch master and slave cylinder and associated pipework.
Clutch Pedal
Brake Pedal
Speed sensor that plugs into it.
Reverse gear switch that plugs into it.
Front (gearbox end) half of the manual prop.
60mm of electrical wire and a couple of terminals.
Plastic gearstick surround for the centre console.
Metal and rubber gearstick surround that bolts onto the gearbox tunnel.
Method (again sketchy memories here)
Jack up the car. Best of putting all four wheels on ramps or even better get yourself a four post lift or over a pit.
Take off the gearstick surround of the auto box. Remove the rubber surround as well and the stuff bolted to the tunnel. Disconnect the switch for the stick.
Get underneath and disconnect the prop from the rear diff. 4 Bolts. Undo the center bush from the car and the prop should slide out and put to one side.
Empty the gearbox of oil.
Get yourself as many socket wrench extensions as possible. Feed them through the gearstick hole to the top two bolts that connect the engine to the box. Then working under the car proceed round and do the rest. Catch the starter motor when the two bolts for that come off.
Undo the four bolts for the crossmember. MAKE SURE THE GEARBOX IS SUPPORTED AT THIS STAGE OR IT WILL FALL ON YOUR HEAD. I lashed a rope around under it through the gearstick hole and around the center bar for the targa tops. I also rested a long wooden bar on rags on the front wings with another rope around it and around the bellhousing of the box. Once all the bolts are undone wriggle, swear and hammer it free of the engine. Then move it out of the way. Take care the engine doesn't pitch forward and clout anything difficult and expensive to repair
Bolt on the flywheel to the engine.
Bolt on the clutch to the flywheel.
Lift the manual gearbox up under and bolt it to the engine and bolt the crossmember to the chassis. The manual gearbox locates in different holes in the chassis than the auto box, but they should be there but may need cleaning out.
Take the auto prop and disconnect the front half.
Take the manual prop and disconnect the front half.
Connect the autobox rear half of prop to the manual box front half
The proceedure for the props is a bit weird as I was doing this on a facelift model using parts from a prefacelift car. We found the props to be slightly different lengths. Either way if you have the entire prop from both cars you can mix and match them to fit.
Offer the modified prop to the gearbox and rear diff and then bolt the centre bush to the chassis.
Plug in the speed sensor and reverse switch to the gearbox. Find the associated plugs on the loom on the car. They are there just have a butchers.
Swap the brake pedals.
Bolt in the clutch stuff and bolt the slave cylinder to the gearbox.
Find the inhibitor relay for the autobox in the main fuse box in the engine bay and remove it, and short it out across the feed to the wire that leads to the ECU.
It should now start up and run a treat ... oh after you have filled the gearbox with oil and bled the clutch.
I may have missed a lot out but it was many moons ago I did this, and it worked a treat.
Im gonna be doing a complete bushing change including rear subframe and diff so thought, hey ive got a chance at a manual box with all related gubbins , prop shaft, linkages etc so if it's not impossibly hard to do why not give it a go 
Thanks for the help 
