Long story – with the question at the end:

I ordered one of these from paddocks – it came with the

• Outer rubber ring (with the split to fit over the crankshaft)
• Inner spring that sits in the outer rubber ring
• Plus the 2 cork T seals.

I had seen on YouTube videos that the inner spring comes in a length, with a hook and eye. So you feed it around the crankshaft and then connect the spring hook and eye. This is so that doesn’t stretch the spring. Seems sensible.

However, the spring that arrived appeared to be in ring already. So my knee-jerk reaction was this was a new type, that you just stretched a little bit over the crank. Which is what I did. Seemed OK.

I subsequently thought about this, and it occurred to me that my spring maybe would have had the hook and eye, but it was already connected and so I didn't see it. And if I had investigated the spring I would have seen it.

So I called up Paddocks – they helpfully had a look at a part in their warehouse, which did have a hook and eye. I decided I ought to order this, as I assume I would have weakened the spring by stretching it.

So far, so good (ish).

But then today, I went to remove the seal i had installed – and the spring doesn’t (!) have a hook and eye.
So it seems that there are 2 versions of the spring.

This ramble leads me onto my question:

• Should I wait for the replacement I have ordered from Paddocks with the hook-and-eye OR
• Can I re-install the one have I got – which has been been stretched over the crank end to install it and remove it.

From what I remember as it has been a while since i did a series crank seal, the spring join on the ones I did were not hook and eye but a taper cone. One end the spring tapered down to a point and the other had a cone.
To undo one had to hold cone between fingers of one hand then rotate the taper with the other anticlockwise.
To do up its much the same, you rotate the taper anti clockwise then place in the cone then the twist of the spring holds it in place
You have to look carefully to find said joint.
I would wait for replacement. Taper the ends of cork seals and get them in with a coating of RTV silicon.

As per your advice, i have decided to wait for the hook-and-eye.
I did remove the seal and have a closer look - from i can tell, the spring on this is not designed to come apart. Despite lots of twisting and wiggling, there was no sign that the join was going to part. I could not see anything on this one that looked like a cone.
Having done all this, I would likely have weakened the spring - so low risk approach is wait for the new one to arrive.

It would be hard to spot a joint of cone type if done up. Agree best wait for new one.