hello fitting my 6 speed in my classic will my manual cable fit in the hole were the electric sensor is . ??????

 

Yes

 

cheers marka have you done this to yours

 

how hard is the job to do,

thinking that if and when my goes, this is the way forward.

what actually is the strongest box?? are all the 5 speeds as weak as each other (not saying that they are weak)

 

Yes; disconnect, unscrew electronic sensor and insert mechanical one.

Not sure which is strongest, I think it depends on how deep are your pockets.

I'm sure I've read the 6sp is good for 600 lbs or torque and may be more with an oil cooler.