When it comes to rust I multiply what I see by at least 3 times.

I'd have a good body tech do a PPI on the car. I'd pay particular attention to the underside of the interior carpeting and trunk and pedal cluster. As well as suspension mounting stress points.

I'd also have an independent mechanical PPI done as well.

__________________
Rick

'85 380 SL (sold)
'85 Carrera Flatnose
'71 280 SL Signal Red/Cognac