Series 3 HELP. My shocks seem too short!!

After 2 years in bits my old girl is slowly coming back together. Rear springs and axle went back on like a dream. Front shocks and axle slotted in nicely but I can't fit my shocks as they cannot stretch far enough. I have gone back over my original pictures and everything seems the same but obviously it isn't.
Take a look at these images and let me know where I am going wrong. Please (before I throw anything else!!)

you need some weight on the chassis

Is it really that simple?

it often is ive found

I suppose under complete conditions the springs will be under the weight of the engine and gearbox so yes, simple it is!

yes

Is that a standard axle? What is the round casting in between the spring retainer U bolts?

Have a look in the book - you need to preload the axle to compress the springs before tightening up the bush pins. The preload distances are measured from the axle to the chassis.

put a jack under the axle and lift to fit shockers for now.