Modern Vespa

Looking for a document/file/link that describes how to replace a GS 160 front shock.
Thanks!

Some discussion here:

1963 GS 160 from the ground up (Page 3)

I was initially very apprehensive, but once I went into it, I realized how easy it is. Once you take the front wheel off, there is a small flat head screw on the back plate that needs to be unscrewed. It's number #34, part number S. 100118 in the Piaggio parts book.

Then, the pivot pin, which this screw holds in place, can be tapped out from the other side with a long punch and hammer. Next, you have to remove the nut and washers at the top of the shock. This can be a nuisance. In the top of the shock dampener bolt there is a slot that has been cut into it. You made need to use a small screw driver or thin piece of metal to put into this slot to keep the bolt from turning. Once the nut and washers are off, from there, to get the shock out, I had to compress the shock spring by hand a bit until it cleared the fork bracket.

After the the top of the shock has cleared the bracket, you can remove it from the swing arm.

And if you need to remove the axle, the castle nut/ring over the bearing is REVERSE THREADED.

Do I need an impact wrench to remove the castle nut on the hub?

Mine had been hammered with a punch, so the notches were pretty bad. There is a special tool out there, but I decided to use a piece of pipe and grind notches in it that match the notches in the nut. I cut the pipe about a foot long and drilled a large hole near the top of it to put a leverage bar through the hole to turn the tool as I held the top of the pipe with the other hand. This type of tool will be very important when installing the new bearings. The new bearings are pressed in by threading the castle nut in the hub and tightening it down. Using a punch and hammer to install would destroy the nut before everything even got remotely close to being seated. Likewise, using a hammer to beat the axle and bearings in would most likely damage the axle and new bearings.

I would not use the castle nut to press the bearing into place.

The bearing should be fully seated in the case first and then the castle nut tightened against it to secure it.

k... I got the castle nut out. Now I can't seem to be able to get the retaining pin at the bottom of the shock. I've removed the screw inside the hub and hit it with a hammer and pouch, but nothing.
Thoughts?

Lots of PB Blaster, wiggle the hub. Hit with punch. Mine was pretty well rusted in there and took some finesse.

Repeat!

Done. Installed a new Mauro Pascolli front shock. Still soft (compared to my MV), but much better than the original I rebuilt when I restored the scoot.
It recovers MUCH better.

Thanks for all the help!