In order to fit a manual transmission to my factory auto C70, I stripped a complete manual 850 for parts, most of which fit just fine, but there is an exception when it comes to pedals.
I assume this is very much a RHD problem as every American thread i can find on this conversion (and there are plenty) says it will all fit perfectly. I can confirm however that for at least Australian market vehicles, 850 pedals are incorrect and do not fit an x70 ..... :(
In saying that, they are relatively easily modified to fit. I will explain as best I can to make it as easy as possible for anyone looking to do this in the future.
First of all, remove the existing brake pedal from the car, this involves disconnecting the clip and then slipping the pushrod for the brake booster off the pedal, remove the long bolt that forms the main pivot for the brake pedal, there is room to slide the bolt all the way out into the space below the fuse box... with a bit of wriggling the pedal will come out.
Comparing the 2 brake pedals, it is obvious why the 850 item will not fit.
The reason it is different is because of the adjustable steering column fitted to the x70, it is different to the 850 so the 850 centre bracket will not fit. You have 2 options here, trim the auto brake pedal down until the manual brake pedal pad fits. The problem with this is the difference in the contour of the pedals, the pedal pad will not sit properly on the cut down pedal. The second option and the option I took was to cut both pedals off and weld the manual 850 pedal to the x70 pedal arm.
BEFORE:
AFTER
brake pedal done.
Clutch pedal is a little more involved, you will need to cut down the pedal in order for it to fit
BEFORE:
First you will need to remove the inner tube and bushes from the pedal pivot tube. Then cut 5mm off the end of the pedal pivot tube (LH end of the above picture, bottom of the picture below), this is important, if you do not cut this 5mm off, it will rub against the steering column whenever you push the clutch pedal.
You will then need to cut it down to 115mm long by trimming the other end, be as accurate as you can with this.
You will then need to cut the inner tube to suit, it should be 118mm, once again as accurate as possible.
And finally cut the bolt that holds it all in place, I welded a nut onto the end of the bolt shank after i had shortened it, If you would prefer you could get a new bolt, the bolt will need to be 130-135mm long from the underside of the head.It cannot be longer or shorter as it will not fit. Reinstall the bushes and inner tube.
Clutch pedal done, this is what it should look like.
Next, remove the clutch/brake end bracket from the vehicle, there is 1 bolt into the underside of the dash and 1 nut onto the brake booster stud.
You will need to use the clutch end bracket from the 850(lower) as it has the provision for the cruise control cancel switch for the clutch pedal attached.
The plastic piece attached to this bracket is different so it will need to be changed over from the x70 bracket(upper)
Insert the new/cut down bolt into the bracket, there is no way of getting it in once the bracket is installed.
Install the bracket in the car, do the bolts up most of the way but don't tighten them fully just yet. Install the brake pedal first, leave the long pivot bolt loose at this stage. Slip the brake booster pushrod onto the pedal and install the clip. Then Install the clutch master cylinder followed by the clutch pedal, the nut for the long pivot bolt can be a little tricky to get in place but it will go, attach the master cylinder pushrod and clip. You can then tighten the clutch and brake pivot bolts and the bolts holding the end bracket in place. You can now install the little clutch pedal overcentre spring, it is possible that the bracket for this is lightly touching the clutch pedal arm, bend it out slightly until it clears.
Done.
Good luck with it