Swap out the EVOs. They're high output ceramic humbuckers and aren't suited to classic tones. You need alnico pickups with their extra warmth.
If you want to stay with DiMarzio I'd get a
PAF Pro for the neck, and either the same for the bridge or maybe a FRED if you want something a little hotter. Classic tones.
As you're in the UK, I'd suggest you check out
Bare Knuckle pickups too. They're all hand wound, made of the best materials and sound fantastic. Their website is
www.bareknucklepickups.co.uk. You say your RG is made of mahogany? I would suggest a Mule in the bridge and a Stormy Monday in the neck for a great all round combo.
