What's the likely problem??

[basher]

After being sidelined for many months and perhaps years before I got it, I have now got the Elan on the road and have covered a couple of hundred miles without too many problems.
One issue I have got is the gearbox.
I am having problems with both 1st and 5th gear - the others are fine.

I can come to a halt and put the car in first and it will 'pop' out into neutral again. Trying to put it back in even with the clutch down can crunch the gears. SometimesI can physically see the gear stick shift as it comes out of gear. Other times its fine.
The other problem is 5th. Sometimes the gear can go in without a problem, other times I am left revving in neutral and again flooring the clutch and shoving it back in hard can (but not always) lead to crunching.

Any ideas what I am looking at here? New clutch/selector/cable/gearboxes (not unlikely if I keep crucnching them).

Any help, gratefully received.

[HJ2]

I would start with checking the clutch cable adjustment (by the manual), and from there have someone at the wheel shifting, whilst you, with removed intake pipe and expansion reservoir pushed out of the way and a flashlight in your hand, check to see if there is any movement on the shiftingcable adjusters. Free play is a nono, and means repairing or better: new cables.

Good luck
HJ2