Modern Vespa

it's a 2014 model and I downloaded a w/shop manual but this is not very explicit.

Sparkplug replacement.
I have never worked on anything so difficult before to change the plug. With the short box spanner supplied it's reasonably easy to get the plug out. However, to get a new one in is
extraordinarily difficult.
I always want to screw the first threads in by hand but if you do this rather than putting the plug in the box spanner, then there's not enough room to get the spanner on. if you can manage to get the plug screwed in by hand, a fair way, then the spanner may go on.
I accidentally dropped the box spanner the first time so learnt that putting a bit of string through it is a good idea.
There's just no room to work if you have normal sized hands. Opposite the plug is a circular cut out in the metal frame but with no hole in the plastic shroud, what is the point?

Is there a better way of getting a plug in? Anyone cut out he plastic and fitted a plug/grommet?

Fuel filter.
No filter in the line from the tank to the injector which would be the case if the line is pressurized by a fuel pump with a pressure regulator. But where is this stuff? The w/s manual says there is only a small basic filter where the line joins the tank but this can't be seen and sounds as if it is non cleanable.

So can an additional filter be fitted? Where is the pump and P R.?

What is the point of that removable plastic panel in front of the engine. Is it for inspection of the head and valves?

patience and small nimble hands. or, remove the fairing, undo the rear shock and and lift the body for access. if you're not about to go to that trouble, then just removing the inspection panel after you've pulled the cap will give you enough room to get in there with a plug jammed into a short length of hose (I use an old automotive spark plug boot).

the filter is in the tank. I'd not worry about adding an additional one.

the panel is for inspection and work in the head and valve area.

EDIt

What i had was the OWNERS manual, not the Workshop manual.

i found this

https://manuals.wotmeworry.org.uk/Vespa/LX125-150ie%203v/LX-S-125-150-3v-ie.pdf