Update a set of SQL statements

dbo.MatchFirstName(@FirstName) and  dbo.MatchLastName(@LastName) 

are table Value Functions(TVFs).

Problem:

In my Update statement i.e Update #Temp after Insert, I want only those rows to be updated that were inserted via the Insert statement used just above it i.e In first Update statment, only the rows that were inserted by selecting from TVF dbo.MatchFirstNumber.

I have my SQL queries like this:

   select @constVal = FunctionWeight from dbo.FunctionWeights where FunctionWeights.FunctionName = 'MatchFirstName'
    Insert into #Temp2(Rownumber, ValFromFunc) select RowNumber,PercentMatch from dbo.MatchFirstName(@FirstName)
    Update #Temp2 set FuncWeight = @constVal, Percentage = ValFromFunc * @constVal 
    select * from #Temp2


    select @constVal = FunctionWeight from dbo.FunctionWeights where FunctionWeights.FunctionName = 'MatchLastName'
    Insert into #Temp2(Rownumber, ValFromFunc) select RowNumber,PercentMatch from dbo.MatchLastName(@LastName)
    Update #Temp2 set FuncWeight = @constVal, Percentage = ValFromFunc * @constVal 
    select * from #Temp2

What could be the workaround for this problem?