I reckon I could set the toe in much closer to the correct setting than it currently is....its that far out! I will get it all checked when I have completed the front, its pleasing to hear that the front should be easier.
You can at least check it with the string method.
In essence, you place two absolutely parallel lengths of string at hub centre height front to back. Each string has to be the same distance from the centre of the hub of each wheel on each axle ( some cars have different track front to rear so you cannot make the string equidistant from each hub ). It's easier if you source some rigid material e.g. wood dowelling just wider than the car and tie the ends of the string to these poles. That way, when you're adjusting the distances from the hubs, the strings will always remain parallel.
On the Spider/GTV it's in some respects easier than on other cars as they will specify angles of toe in/out. The Spider/GTV is specified in mm so you don't have to do any trigonometry.
Here is how it is done using the rear wheels as an example :
Measure the distance apart of the two lengths of string. Call this Z.
Measure the distance from the leading edge of the wheel ( using the lip at the tyre ) to the string on both sides. Add these together and subtract from Z. Call the resultant figure D1.
Repeat for the trailing edge of the wheel. Call this D2.
Subtract D1 from D2.
Up to and including 1997, the resultant figure should be 2.5mm +/- 0.5mm. For 1998 and after it is 3mm +/- 0.5mm.
Because the wheels are independant of each other and not tied together with a steering rack, you can now modify the technique to ensure each wheel is 1.25mm +/- 0.25mm.
The front is similar except you have to centre the steering wheel and any adjustment must be done on both sides.
The other difference is that the front wheels toe-out
and not toe-in like the back wheels.
For the front wheels, up to and including 1997, the resultant figure should be -
1.5mm +/- 0.5mm. For 1998 and after it is -
2mm +/- 0.5mm.
I will be giving this a go myself shortly. All I need to get is some good quality thin string. The string I have is too rough and thick and I reckon cotton is far too weak.
EDIT : See section 44 page 20 in the workshop manual for more info.