401Ks in Spain

Hi

I am a US national resident in Spain and I and my wife are both set up as freelancers. We have recently set up individual 401ks though we are more interested in individual roth 401ks.

My queries relate to if / how wealth in 401ks - and the interest and dividends generated -- are taxable in Spain before one has retired. More specifically the questions are:

[1]Are individual 401k and / or roth individual 401k pension plans declarable in the modelo 720 (assets held abroad)?
[2]Are individual 401k and / or roth individual 401k pension plans declarable in patrimonio (wealth tax)?
[3]Are individual 401k and / or roth individual 401k pension plans income declarable in IRPF (income tax)?

If anyone has any experience of this they can share, that would be much appreciated.

Thanks