I'm no expert, but I researched this pretty thoroughly because I considered doing the conversion, too.
Besides the rack, you need:
- Manual steering shaft (944online.com sells a converted one for $295
http://www.944online.com/cgi-bin/ASI_Store.cgi?Product+skukey_1220892424+9441+steering-9441- Steering rack boots
- Steering rack bushings
- Inner/outer tie rod assembly
I decided to keep my power rack and "convert" it to manual by:
1. Remove all the old p/s attachments (pump, reservoir, hoses, etc.) to lose weight
2. Drop the rack/tie rod assembly from the cross member/spindle
3. Remove the p/s pressure lines
4. Plug the bottom hole with BMW oil drain plug part #11 13 1 742 994 and copper gasket (both from a 1994 540i). This fits this hole perfectly and is about $4-$5 each from the dealer
5. Fill top rack hole where hoses used to go in with p/s fluid
6. Move the rack all the way to the left/right and let the excess fluid drip out
7. Plug the top hole the same way as step 4
8. Reinstall rack/tie rod assembly
I got this from
http://944spec.org/944SPEC/component/option,com_fireboard/Itemid,30/id,2411/catid,13/func,fb_pdf/I really like the results...less weight, no leaks, less parasitic drag on the engine, better steering feel and accuracy. The only drawback is increased steering effort in the pits (I grew up with manual steering cars so this doesn't bother me).