Driving with tail lift horizontal

Hi

Is it legal to drive with the tail lift in a horizontal position?

A friend asked me if I could collect some logs to take to a sawmill. The logs are 7m long and the inside length of my wagon is 5m20.

If I load them with the tail lift raised but horizontal is this OK? Like this they will extend about a foot past the rear of the tail lift.

What sort of extra lights, warnings, etc would I need to stay legal, if indeed it is possible?

The regular tail lights would be visible by cars behind but not to wagons or buses.
I suppose at the very least I’d need an extra set of rear lights visible from higher up?

Thanks

“Z”

PS. I’m in Finland (EU) but I’m assuming for the purposes of this question that any legislation regarding this would be EU-wide ie the same both in the UK and Finland…
I’ll also find out independantly what the situation is here before agreeing to actually do the job.

It isn’t how far it extends past the end of the tail lift but the rear of the vehicle. Not sure of the exact distances but I think it’s 1.5 metres you’re allowed with only needing marker boards.