Pulleys or Balancer

[Old Chevy Mech]

Looking for some wisdom here....

My "new" 70 chevy C/20 4 X 4 came with manual steering (worn out). I've bolted on the new PS box & pump with no problems, all fit nicely. The truck originally had a 350, but the previous owner swaped it out and put in a Small block 400. Thats the situation.

Here is where it gets dicy. (I'm not being lazy just seeing if I can save a little time in resolving the pully misalignment problem.) Nothing lines up to the crank pulleys, so I am wondering if that harmonic balancer isnt pushing the crank pully's out too far? (It looks that way) The Alt pulley is on a stock bracket and it is back far enough to line up with the water pump but not the crank pulley.

So, can I change the Harmonic balancer on a SB400 to one that allows the pully's to sit back closer to the block and hopefully line up with the alt pulley?
Has anyone ever had this problem with the crank pulley not sitting back far enough?

Thanks

Frank