Bicycle Mechanics - Changing shifters without completely removing cables

I'm about to start swapping out a set of Ultegra STI (ST-6600) shifters for a set of Dura Ace shifters (ST-7801) on my road bike. The cables and bar tape are in good shape, so I was wondering if there is any way to swap out the shifters without totally removing the cables?? Looks like you have to thread the cables through holes in the shifters and then run them all the way to the caliper or derailleur, and in order to remove the shifters I'd have to detach the cable from the caliper or derailleur, cut the end cap off where the cable, and totally pull out the cable. Anyway to avoid having to do this?

no other way sorry about that.

no other way sorry about that.
Correct. If you unwrap the bar tape carefully and don't fray the cable ends, you should be able to reuse them.

Don't cut the cap off the end, you should be able to squeeze it with pliers or a crimper, to squish in the wider parts of the crimp. Then it slides back off the cable.

Pulling out the cable from the housings is easy, and reinstalling it won't be a problem if the end of the cable isn't frayed.

Don't know how old your cables are, but it is not very expensive to buy a set of inners and replace them. Reusing the old cables doesn't always work out so well. There are those pesky crimp areas where they were attached to the brakes or derailleurs. They may unravel and be difficult to route back down the housings.

This is a good time to overhaul your cables for more years of trouble free service.

Thanks for all the responses. Yeah, I figured there was no other way to do it than to competely remove the cables. I was hoping to not have to re-adjust my derailleurs as I'm sure the shifting will be off once I replace the shifters and re-attach the cables.

Thanks for all the responses. Yeah, I figured there was no other way to do it than to competely remove the cables. I was hoping to not have to re-adjust my derailleurs as I'm sure the shifting will be off once I replace the shifters and re-attach the cables.
You shouldn't have to reset the limit screws but you will have to readjust the cable tension.

If you're upgrading to Dura Ace and paid $$ for them, I see no reason to save $20 by reusing cables and housing. Save them for a cheaper beater build. Might as well replace it all.

If your cable is fine, your cable is fine. Dura ace or Schwinn Approved. Drip a bit of tri flow in your housing to give it a little lube and protection, and wipe your cable down with a bit of it too. Pull cable tight on derailleur and check shifting. Might be fine, otherwise adjust cable tension with the stop screw on derailleur where your housing stops.

If the cables are older then a year, I would replace them. Shimano brifters have a habit of breaking cables inside the shifter, near the head, and jamming an otherwise completely good shifter. Shimano won't fix this problem other then recommending changing cables every year.