It's likely your 350 engine has the long water pump. It could be possible to install a short water pump and use the pulleys and brackets associated with that set up. The standard 350 crank pulleys are fairly deep which pushes the pulleys closer to the front cross member. The pulleys that came with earlier (283/327) engines are flatter up against the balancer and may solve your problem. You would need to match up all the pulleys for the water pump, PS, & crankshaft along with the related brackets.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine