Have you looked into electric power steering (don't know if they are strong enough for the big trucks)? It might make it easier by keeping the original box...
Mike B
Mike Boteler
1956 Chevy 3100 Resto Rod 1952 Willys M38 Army Jeep 1983 Jeep CJ7 Laredo 1984 Jeep CJ7 +++++ Silver Spring, MD