There is a little sleave at 5th gear that fails. If this is the case full rebuild needed.( this is only a guess.) The sleave was made stronger in later years, can't remember when though.
left side looking from front of transfer is a flat bolt head about 19/22 mm unscrew spring and ball is behind. I used a washer as a packer until I got around to ordering new spring and ball from one of the internet parts shops . eg megazip
Rep just replaced mine $1000 plus paint. I had been pumping lanolin into mine so the bottom was good but the top rusted. Yours looks really good and from pics rust free. Must have been in outback Queensland.
Tidy vehicle well done. Can't wait to help spend all your money ,turbo ,suspension, seats the list go's on. First job take off sun visors and spray your favourite rust proof through screw holes.
I put after market Alpine speakers in mine, sounded much better. You could also hook them up as extension speakers for 2 way radio. I did that with my HJ75.