67L78 clutch linkage

[L78Kiwi]

Hello, I hope someone can please help. I bought a clutch linkage kit for me 67L78 (this is a nut and bolt rebuild for a L78 that has not been on the road since 70).

This is an aftermarket kit. The linkage from the bottom of the belcrank to the folk appears to be too short. When I look at the factory assembly manual it shows the linkage supplied as being for an L6. In the meantime (for example) Heartbeat city shows this kit with the factory assembly manual L6 rod as being correct for all BB applications.

I have the short clutch fork and the long series throw out bearing. I just changed from the short series as it didn't have the reach. With the long series replacement it is now engaging properly but the linkage suppled is frankly flimsey and adjusted to the max to get good engagement.
At this point I am considering fabricating a sleeve (similar to that shown in the factory assembly manual for a V8) to give the linkage rod the reach needed. What I would like to know is.

1. Have you had a similar experience and can you offer some useful advice?

2. Is the linkage for kit suppied actually correct and does my mod seem logical?