Word of warning, the 19.5's would not fit over the rear drums of my 48 4400. They were off of a mid 90's 4500 Chevy. I ended up refurishing some 1950 6400 wheels so I could get the wider rims so I could buy 8.25 - 20 tires. It called for the 7.50 - 20's but they are expensive,
Good luck,
Scott