I would run them outside then - clear run to the foredeck without unclipping. If you can reach the main and reefing without unclipping all well and good, if you can't, you would have to unclip and relocate on a closer fixing point anyway.
There has been much discussion on this subject. The question is ... Do you wan top stay on the boat or just attached to the boat but possibly in the water. Half way between would be pretty awefull. If you want to stay on the boat then you need to be attacherd on a tether to a point near the centre of the boat. The harness attachment can be on the chest.
if you are willing to accept going into the water the jackstays can be used with a long tether. However be warned a chest attachment pulling you along at 6 knots is very bad. (face full of water) better a back attachment that pulls you along on your back in reasonable comfort back of head taking the water pressure. You will find you must rely on the crew to stop the boat to pull you aboard.
So if single handing you must stay on the boat with very short tethers while multihanding if you are willing to take the risk (perhaps reasonable) then a long tether and jackstays are Ok. ie jackstays outside of stays.
Of course the worse scenario is no attachmment which would suggest jackstays outside the shrouds.
I suggest you go out on a warm day and try the jackstays by falling overboard. You will quickly get a better perspective on the subject. regards olewill