You might be able to get everything back where it should be, but a pro would be a much safer bet.

Since it was sitting there for a long time, there may be clean, or unfaded spots in the finish to indicate where the bridge used to be. If there are wider rollers or notches in the bridge saddles on one side than the other, that shows which side the thicker strings were on.

The spring is only useful with the tremolo. You don't need it if you don't use it.

I recommend taking it to a good tech for a full setup. After a long time being out of service, it should be carefully inspected by someone with the right skill set.

Best of luck to you.