360 engine vibration

Ive spun the converter all the way round and cant see any welded on weights.

How would I check the engine is magnum or premagmum. I suspect the engine is a fresh rebuild or crate engine as all the fixing look new and i doubt it has done any mileage.
I off to the states next friday 21st oct for 2 weeks road trip ( south Cali) , so would be good to arrive with a shopping list :)

dont look at the wiring ( Arrgh) and the air filter got binned straight away!
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