How to handle reimbursement for separate funds used to pay down community dwelling mortgage?

During her marriage Texas wife has applied inheritance from her father toward paying down mortgage on community dwelling. The executor has the origin and tracing of the funds well documented. Surviving spouse intends to exercise his life estate rights to occupy the dwelling as homestead.What is the right course of action to for the Estate to request reimbursement from community to the Estate: 1. file a law suit against the surviving spouse now or wait until the surviving spouse passes away (which removes homestead restriction against partition of community dwelling and make equity available for reimbursement)? 2. file a claim with surviving spouse’s estate executor once the surviving spouse passes away? 3. are there any statue of limitations to file #1 or #2 above? To avoid expected difficulties of money judgement executions, the executor prefers reimbursement be part of “just and wright” division of the estate.