Sportrak gearbox issue, can't get 5th or reverse!



I have to look at a gear box problem for a friend.
Its a J reg 1.6 petrol.

Before he was going on holiday he wanted to check the gearbox oil. But instead of removing the level bung, he removed a large cap head bolt above and to the left of it.

It was a large cap head (takes about a 12mm allen key). There was about 30mm of thread then a pin/shaft on the end of it again about 30mm long. He put it back in and can't get 5th gear or reverse. The gear stick feels fine through 1-4 gears but wont drive in the other two.

I can only assume something pivoted on the pin and has now droped into the gearbox.

Does any one have any ideas or a manual who can look up what the pin may have done?

A bit of info or a diagram would be nice before it turns up in my workshop friday!

Many thanks