I made a steaming tube out of 4" ABS and made steam using a wallpaper steamer hooked up, soaked the wood for 3 days in the steamer. Steamed the wood ( 15/16" thick ) for 4 hours.
Use ASH , its easier to bend and less likely to crack,. make sure you have an extra pair of hands to apply clamps. You need to make the pattern 5% narrower each end to account for spring back once its removed from pattern .
Have your ash cut into 1/2" thick strips, makes it a lot easier to bend the wood without breaking. When I do my roadster top bows will use that method instead of bending the 1" thick boards.
mike lynch