A customer recently came to our shop with a big smile about his discovery on the changeover for his 1937 Chevy 1/2 ton. He had changed his engine to either a V8 or a 235 six-cylinder. The closed drive shaft system had to be removed! After researching the local salvage yards, he discovered the perfect replacement. On a 2005 Chevrolet Colorado pickup, he found a rear end with 6 bolt drums to match his front originals. The leaf spring saddles were in the correct position. The backing plate to backing plate was only one inch wider (1/2 inch per side). It worked for him, it should be correct for you if you update your driveline.