Thx Ulysses, that link is a great step by step tutorial
But what it doesnt show is what modifications u need to do to your spear...
Well, that's fairly uncomplicated:
1. Unscrew the shaft butt
2. Remove everything from the original shaft (ss ring, spring, slider), unless it's a Devoto shaft
3. Install in the following order:
3.1 Devoto slider (for line attachment)
3.2 shaft o-ring
3.3 Maori slider (sealing cylinder)
3.4 additional o-ring (to prevent premature breaking of the Maori slider)
3.5 Maori ss ring
4. Screw shaft butt back on (use teflon tape or appropriate glue on the thread first)
Cheers,
ulysses