Dynamic SQL with nvarchar(max) variable (again)

Question

I have read about a dozen articles here and I am still stumped with this issue.

I am building a dynamic select statement that will update a view on a monthly schedule.

set ansi_nulls on
go
set quoted_identifier on
go

alter procedure [dbo].[Proc_Name_SP]

as
begin
set nocount on
set quoted_identifier off

declare @dbname varchar(10), @schema_id int, @schema_name varchar(10),
@jacro varchar(10), @rec_cnt int, @tot_rec int
declare @SQL_Main nvarchar(max), @SQL_Final nvarchar(max),
@SQL_schema nvarchar(2000), @SQL_Union nvarchar(max)

declare iteration cursor global static for
    -- Begin statement for cursor array
    select distinct db, code 
    from linkedserver.db.schema.Directory
    where current_stage = 'live'    
    order by db
    -- End statement for cursor array

-- get total number of cursor iterations to know when to stop
-- "union" statements
select @tot_rec = count(*) from (select distinct db, code 
                from  [linkedserver].db.schema.Directory
                where current_stage = 'live') as cur
    -- begin loop               
    open iteration
        fetch first from iteration into @dbname, @jacro
        while @@fetch_status=0 
        begin
-- the schema used is not consistent. Because of the linked server it was
-- necessary to get the Schema_ID from the sys.tables and then pull the 
-- schema name from sys.schema
    set @SQL_schema = 'select @sch_id = schema_id from [linkedserver].'+@dbname+'.sys.tables where name = ''Manuscript'''
    execute sp_executesql @SQL_schema, N'@sch_id int OUTPUT', @sch_id = @schema_id output
    --print @schema_id          
    set @SQL_schema ='select @sch_name = name from [linkedserver].'+@dbname+'.sys.schemas where schema_id = '+cast(@schema_id as varchar)+''
    execute sp_executesql @SQL_schema, N'@sch_name nvarchar(10) OUTPUT',  @sch_name = @schema_name output
    --print @schema_name

    --building Select statement
            set @SQL_Main ='
    select jcode.Code as BILLING_ACRO
    ,s.start_dt as BILLING_DATE
    ,cmpt_ms_nm as MANUSCRIPT
    ,isnull(jcode.billing_type, ''reviewed'') as Billing_type 
    from [linkedserver].'+@dbname+'.'+@schema_name+'.Manuscript as m
    join [linkedserver].'+@dbname+'.'+@schema_name+'.Step as s on m.ms_id = s.ms_id and m.ms_rev_no = s.ms_rev_no
    join (select j_id, Code, billing_type from [linkedserver].db.schema.Directory where db = '''+@dbname+''') as                                                                      jcode on jcode.j_id = m.j_id
    where jcode.Code = '''+@jacro+'''
    and m.ms_rev_no = 0 
    and s.stage_id = 190
    and isnull(cmpt_ms_nm, '''') <> ''''
    and s.step_id = (select min(s2.step_id) 
    from [linkedserver].'+@dbname+'.'+@schema_name+'.Step as s2 
    where s2.stage_id = 190
    and s2.ms_id = m.ms_id
    and s2.ms_rev_no = m.ms_rev_no)
                    '                            
        set @rec_cnt = isnull(@rec_cnt, 0) + 1
        if @SQL_Union is null
        begin
        set @SQL_Union = @SQL_Main
        end
        else if @tot_rec <> @rec_cnt
        begin 
        set @SQL_Union = @SQL_Union + ' union ' + @SQL_Main
        end 
        else
        begin
        set @SQL_Union = @SQL_Union + @SQL_Main
        end 
        --print @rec_cnt
        fetch next from iteration into @dbname, @jacro  --next database

        end -- while @@FETCH_STATUS=0

close iteration

deallocate iteration


-- build new view
print len(@SQL_Union)
set @SQL_Final = '
ALTER VIEW [dbo].[View_Name_VW]
AS
'+@SQL_Union+'
'
execute sp_executesql @SQL_Final

--grab string variables to table for troubleshooting
insert into Output_SQL(SQL_Final, SQL_Final_Len, SQL_Union, SQL_Union_Len)
select @SQL_Final, LEN(@SQL_Final), @SQL_Union, LEN(@SQL_Union)


set nocount off
end
go

I have read that others have had problems with this type of truncation and I have tried multiple suggestions but in the end the I am getting capped at 68274 in this code with nvarchar(max). For troubleshooting, I am saving the results of the variables and the len of these variables to a table to eliminate the SSMS cap on the display of strings.

I have tried cast(@varible as nvarchar(max)) on the right side of the = sign. I have changed the data type lengths (as the select that is being built is not that large, it is just large after it has been union for each unique customer)

I am open to any suggestions as I have tried many variations of datatype declarations for these variables.