I wouldn't stress (excuse the pun) too much if you can't locate the original engineering details
Your engineer should advise you of the best way to replace the columns
Apart from the…

Superlim112
You should have got a Structural Engineers report before you purchased it
They would have advised you the structural repairs are going to be…

If I was you I would be very concerned because the plans do not show posts but solid brick piers and because of the corrosion the posts are structurally compromised.…