1996 GTI drive shaft problem

[KartAnimal29]

2 years ago I replaced the drive shaft and the OEM prop. I picked the ski up really cheap the year before and knew the drive shaft wasn't going to last long. I ended up going with a Solas impeller. I really haven't been out on it much during then 2 year's and the last few times I have noticed a small vibration. This past Wed me and a buddy went out for a bit and I spun the drive shaft on the impeller. Got back to the house and we took it apart and we find that the drive shaft wasn't in all the way on the impeller. A 96 GTI takes a 17 inch shaft, the motor is lined up but there is about a 1/4 play on the shaft. Here is my thinking. 1 the Solas impeller isn't as long as the OEM hence it doesn't go all the way in or 2 I have an off year and I need the 17 1/4 drive shaft.

Any help on this would be great

[Tiny]

Do you have the rubber bumpers at BOTH end of the driveshaft???

[KartAnimal29]

Yes Tiny