Do you have an example? Objects (especially ones that can be broken down into primitive shapes) have perspective/vanishing points too. Else you have to eyeball. I think when translating 2D designs into 3D, one should focus on capturing the "essence", so the 3D model stands on its own and doesn't fall apart from certain…
Outside application and or plugin, probably best since some time has past to jot this issue down for a later date to review and look into for next time and just go ahead and manually do it, this is a good example of why planning ahead is important. Blender might help with this idk about blender to much though & jumping…