If you have FMAdvanced generate a Database Design Report.
I tried that first, but I have some scripts used solely as script triggers - these aren't shown as 'in use in the report, unless i am misinterpreting the report? I assumed i would just note down which scripts have nothing entered next to the lines below
Layouts that use this script Scripts that use this scrip
and then remove them - however I noticed that some scripts used in triggers are not shown to be.
Haven't got around to looking at fields yet.