Headlamp cowl

[nick61]

I have a 95 chim, noticed there is no sealer around the headlight cowlings. It results in being able to see the unpainted edge of the cowl, which against the body colour-copper green is noticeable.
Does it need it??
If so what sealer is used??
Can it be done properly without removing them??
Any info would be appreciated.
Thanks
Nick