Thanks to both of you for your replies, I've watched a few videos  on utube, of the approach and exit of the Vielha tunnel /N230 and  Im allot happier now,I've been on that road many years ago,on the Spanish side.but thought it was like the N260 a road that I woundnt want to drive a big old van on,saying that the views on that road are breathtaking.
I've already booked ferry ,Newhaven/Dieppe £200 return,around £150 cheaper than Portsmouth/Le Havre,would have been cheaper, if van was a few millimeters shorter😤 but best to pay now than be caught out once there!
Thanks again
Phil :D