Lotus 5 speed. Is this normal?

[gjz30075]

I've just acquired a rebuilt Lotus 5 speed box and noticed the back half of the input shaft splines look worn.
Looks like a 5k rpm clutch drop and the splines get ripped, or something. However, looking through
Alex Black's gearbox swop thread, this may be a normal thing.
Any issues here? Methinks not, but just checking.....

[Mick6186]

Hi,
my 5 speed box is currently on the bench in pieces . The splines on mine (75000 miles) are worn the same, but worse so this appears to be 'normal' wear with age.
My box is out because I'm trying to get to the bottom of why it will not go into reverse once 5th gear has been selected. I've never taken a 5 speed synchro box to pieces but there appears to be a lot of parts!
I'm hoping there is going to be a fault with the convoluted reverse/5th selector mechanism,
Mick.