Yeah, it's not so much that the spring won't go that high.. if I hold it up, the top protrudes out as much as the old one, with room to fit the air line, etc. But as soon as I let it rest, it drops back down again on the R-clip.
Left it running for an hour, nothing. Bags as saggy as an old womans pups. Have unclipped the bottom of the springs, compressed them back into their original shape, held them up and re-fitted the air lines - bit happier with how they've gone in now. Trouble is I feel like as soon as I try to clip the bottom in place, it's going to sit all wrong at the top again. I've had enough tonight, losing light and hungry for dinner. Will tackle again in the morning. Unless anyone in the Canvey Island area fancies having a bash?