Legal Question in Real Estate Law in California

First, you should verify that this is even necessary...it's possible the reverse mortgage could have a spousal provision. If necessary, and it probably is, you'll have to negotiate with the lender. Changing (and probably extending) the time frame for the lender's recoupment of its investment is a significant concession and preumably would affect the fundamental terms of the original reverse mortgage.

Major modifications to mortgages can affect the priority of the mortgagee's (lender's) lien and the lender will be cautious to make sue it is not inadvertently subordinating to someone, if they are willing to proceed at all. That would mean a new title search.