Actually Johnson left office in 1969 and submitted the 69 budget to congress in the spring of 1968.Johnson left office with a surplus, something we wouldn't see again for 40 years.
Wrong.
$27B deficit in 1968. The highest since WW2 to that point.
The 1969 surplus in nominal dollars was 3.2 billion, 20 billion adjusted for inflation.
History of Deficits and Surpluses In The United States
Red herring. He left in Jan of 1969, not enough time to have any effect on spending that year. 68 was the last full year of his term.