Hi Chris
I started fishing a 'virgin' lake a few years back, sounds very like the one your planning to fish, with carp stocked a few years ago, anyway i found that stalking with a float and a worm was an absolute killer! The carp will be very spooky so you have to take time getting into postition, being quiet and out of site, but i found they would feed quite confidently seeing as they wernt fished for previously. i would creep round a few likly looking swims and introduce a handful of maize, pellets or groundbait just feet from the bank. Then go and set up a simple rig, a float (check out self weighted puddlechuckers, there great) then a braided hooklink then either worm, bunch of maggots, maize or give boillies a try. I would then go and have a look for signs of feeding, lillies moving, clouds where the bottom was disturbed, swirls etc. wait for the fish to move out of the swim, introduce the hookbait, then they should be back in a matter of minutes.
Just a tactic i found works, and still does now. Not as good as it used to be, so id give that a good go!
Good Luck! Dan