Just done it and its a fair bit of work.
![](./images/smilies/spacer.gif)
Use search and there is a step by step guide, maybe on MR2OC.
![](./images/smilies/spacer.gif)
Basically need to remove the bits that bolt to the floor off the mk3 rails and replace with the bits off the mk2 rails.
![](./images/smilies/spacer.gif)
You can use bolts to hold them to the rail, until you are happy and sure that everything works then just a spot weld.
![](./images/smilies/spacer.gif)
There is a front and rear roller on each side, I've lost the rear roller, so seat travel is best done with you not sat in the seat, although that could just be the method I followed.
![](./images/smilies/spacer.gif)
No problem if you are the only driver as you don't need to move the seat.
![](./images/smilies/spacer.gif)
Does look good and seems like there is more room in the cabin.
![](./images/smilies/spacer.gif)