About 6 months ago I hurt my 915 gearbox while trying to do a "burn-out" having some fun... Besides me obviously being a dips**t and needing work there, I need to fix the issue with my car.

Here is my dilema.. 1st gear is not useable. I can use 2-5 and reverse. The car has not been driven since I did the initial damage except for today as I decided to give a repair a go. With the car idling, the box will feel like it shifts into 1st, but when the clutch is engaged the car remains stationary. If I try to shift the box into 2nd, I can feel the gears start to grind slightly, but it will not move beyond that point. I can only get back into neutral whith the car off and by rolling it backwards or forewards a bit. After it gets back into neutral, the car shifts fine for nearly regular driving.

Any usefull suggestion will be greatly appreciated. No need to comment on my driving skills or brain power please.

 

Not much to suggest, you are looking at a tranny rebuild. Probably will have to replace 1st gear, and some bearings and syncros.

 

Very well. I was told there is a way to "align" the shift selectors through an inspection plate on the trans. Is this possible or is a rebuild my only option? What usually breaks?

 

There is an inspection plate on the trasaxle, but I have never tried to align the d tents through that port. To do that properly, it is done by pulling the tranny apart. Hopefully your R&P is ok.