Insuring a Gibraltar registered car in Spain.

I have bought a Gibraltar registered car in the UK and plan to drive it from the UK to our new home in Marbella in December. I will then register the car in Spain immediately.

My problem is that I cannot find a Spanish insurer that will insure it on the Gibraltar plates pending Spanish registration.

I can't find a UK insurer that will insure it on Gibraltar plates, they need it registered as a UK car first (not economically or time viable).

I can't find a Gibraltar insurer that will insure it unless I have a registered Gibraltar address.

Ideally, I need a Spanish insurer that will insure the vehicle either on its Gib registration or on its Chassis Number, whilst on it journey from Santander to Marbella, pending the registration in Spain. I have already engaged with a Gestor to do this as early as possible after my arrival.

Any help or advice would be graciously received.