AndyG
Here you are, WT368 at Kuantan in 1964. Note
'lo-silver' undersides*, white serials and sqn code and
black gunpack (gunpacks never got re-painted to silver).
* Ask Steve.
Also remember they had a 14 Sqn crest and bars on the nose.
Hobby
Not grey undersides, silver. B(I)8s didn't have underwing roundals.
But you're right about serials and sqn codes being black, but that shot is in early/mid 1970 just before they conveted to Phantoms.
With B(I)8s, camo schemes, serial sizes and colour, sqn codes crests and badges were changed frequently and often. The only really definitive thing you can say about it is they all started off with black undersides and then all went to silver.
The sqns equipped with the 8s were 88Sqn (the first with 8s, then re-numbered to 14); 59 Sqn (re-numbered to 3), and 16 Sqn.
I have a growing B(I)8 set of pages on my Canbera Web Site,
http://www.bywat.co.uk/gallb8.html.
Hope this helps.
.