Remove aerial base?

Ok this is probably a really dim question but I need to remove my aerial base from my NA.

I’ve taken the aerial mast off, unscrewed the 10mm nut holding the bottom of the base in place, and unscrewed the top section (with notches as in the picture below)

But underneath that notched section is a thick shaped back part that sits on the wing that I cannot budge.  Does anybody know if this is meant to unscrew or just pull off? It seems pretty stuck fast but it might just need a squirt of WD40 or something?

 

Any ideas?

base

Thanks in advance 

It unscrews you may need to tap it round with a screwdriver in one of the notches

Thanks Kwakers, I can get the top bit off with the notches in, its the bit underneath that I am struggling with…

 

 

If you have unscrewed the chrome top nut with the two notches you should just be left with a spacer made of black plastic with a rubber sealing washer at the base. It should lift off but may have stuck itself to the wing.

Sometimes people respray the wing without removing the aerial so may be stuck with paint or lacqeur. 

Undo the securing bolt in the boot and use the main  base section as a means to loosen the spacer.

The top part with the notches in it is what holds it to the wing!! sounds like its just corroded to the wing ! bit of penetrating fluid then and it should just pull down into the boot space.

So not quite as easy as it seems…

take the notched top off the aerial base and you can get the aerial out (I just tapped it out using an old bolt as a drift) but you are left with the black hard plastic section that sits on the panel like so

 

This appears to be attached to the wing with another nut only accessible from inside the boot.  Looks like this and looks like a pig to get off!

 

Think I’ll work round it for the time being!