Could you explain why your license / registration / insurance would be invalid?
Asking as we went through a similar deal a while back (resident of MN building new place in ND [year out]; sold MN place then stayed at lake, in RV and various rentals across the US until the new place was completed). Basically went mobile until the new place was done.
Anyway, we couldn't get ND residency until we had a physical address in the state. For the duration between MN sold and ND available we left our residency in MN via a PO box. Changed all addresses to the MN PO box including our insurance and licenses. None of that behavior invalidated insurance, registration or licenses.
I had same issue about 3 years ago on our 1997 WIA 64 while camping at Myrtle Beach. Found a truck shop there and the owner and his two mechanics weni over every ground on the engine and in the dash. Cleaned them all and Deoxed. No problems since.