New engine, old cast crank pulley? Pulley Qs

[demian5]

So some have read my story of needing an engine for my 70. I went with a retro kinda look and am wrapping up the install. I kinda wanted to update the pulleys, so I tried some chrome ones I have, but the power steering only aligns with this cast pulley that came off of the old motor. I did clean it up and paint it.

My concern is that this is a bit of weight hanging off the front of my new motor, should I be concerned about this for harmonics, balance, etc...? And is this a 327 pulley or a 350?

I could probably get an offset PS pulley, a different lower pulley and be done with it.

I also have in my stash a 3 groove aluminum pulley I could use for less weight, but my concern with that is the water pump and alternator will be turned too slow and not cool/charge efficiently.

You can see the differences in the pictures.

Thanks for any assistance.