Silhouette Tuning

[Klimax]

Can I tune a Silhouette Bass like this: (low to high)

A-E-A-D-G-B or A-E-A-D-G-C
(E is the E of a standard 4 string bass and the first A is the lower string of a 5 string bass 1 step lower(very low))

Without cause problem with the neck?

Thanks

Klimax