So I potentially got a line on a 454 to replace my tired 235. I've read lots of the old posts about this swap, but still have some questions.

What is the weight difference between a 454 and a 235?

Can I keep my original steering box with the stock 454 exhaust manifold or do I need to get some fancy ($$$) headers?

Thanks for any answers and let me know of anything else I might have missed!