found this advert in The Beano of this issue..
A nice cat like Korky by James the last panel...But the top three is by Bill...maybe the original plan was the cover to just be Korky filling the whole page?!
Looks like Bill Ritchie to me, Peter: very unusual!
I can't remember any other instance of Bill 'ghosting' although he's not really hiding his style [on frame 3 especially].
The main picture with the 'whizz-bang' or whatever looks like Crichton job, though.......
Nice find! Spy
Reading the wiki it shows when Charles Griggs starts in
Charles Grigg from issues 1052 to 2116 (January 20, 1962 to June 12, 1982.)
But has I've proved on the last post Charles was drawing the odd Korky before that date!
Image taken from comic vine...reloaded up on here