Body experts, please help.

[FormerMember]

Posting this here, because it's a 71 cab that had cab corners and rockers welded into. Got it from another member and this project's really killing me.

How do I fix this?

You're looking at gaps at the cab corners and where the rockers were welded in. This was supposed to be a turnkey cab and I truly suck at body work.

I shined a flashlight through to make it more visible. The passenger side has the same gaps in the front the driver's side does. I can stick my hand through the gaps in the passenger side cab corner.