If you are trying to run a mech and shifters from different companies and want them to index but they just won't try this!!!
Where the inner cable bolts to the mech undo the bolt, then put the cable on the otherside of the bolt to where it would normally go.
This has the effect of changing the cable pull given by the shifter.
Therefore in my case, trying to run shimano ultegra shifters through a campag veloce 9 speed mech over a sachs maillard block, the bottom three cogs indexed okay and it got progressivly worse until the top of the block where it indexed again but one whole cog out meaning that top cog couldn't be accessed. Changing the cable clamp position over to the inner side of the of the clamp bolt and it worked miraculously!!!!
Somerset, like 'Heartbeat' with newer cars!
Retro MTB: 1992 Cannondale M1000 Deore XT M730. 1992 Raleigh Dyna Tech Quantum Deore XT.
Retro Road: 1992 Eddy Merckx Corsa Extra Telekom Shimano 6500 Ultegra. 1993 Dyna Tech Ti Campagnolo Athena 8 Ergopower.
Modern: 2004 Wilier scandium Ultegra 6800. 2014 Wilier GTR Dura Ace 9000.