Attaching table rail?

[Flanners]

I have a rear conversion with seats/storage over the rear wheel arches and a table rail on the kitchen unit. I have purchased another rail to go on the o/s of the van so when the seat is swivelled it allows more table location options so into the chassis not into a kitchen unit.

I have the rail and fittings but can someone recommend a procedure/items needed to attach the rail to the van chassis/trim securely?

[Bob]

Ours is fixed to the trim below the middle window with self tappers.

Just right when sat on the bench seat whichever way it's facing.

Obviously don't use a spirit level, either eye ball or tape measure.

[Flanners]

Cheers, will have a go at it tomorrow.