I've had good luck doing just that. Just be careful removing the end fitting to reuse. A better option is to locate the end fittings at a parts store and building brand new lines yourself.
I use a heat gun on low to warm the line just enough to allow the fitting to be forced in. Keep the heat...
If you can get them out, they appear to be working.
Make sure that the engine is tuned up well. Catalyst failure is caused mostly by poor engine combustion. Make sure the plugs are in good shape. And I'd consider getting the injectors cleaned.
I recommend NTK sensors.
Although you should really watch b2s1 and b2s2 at the same time. While loaded in drive at 1500rpm.
You'll want to take it on a moderate highway run at 55 or so for like 10 min before hand. The b2s1 should switch between .2 to .8v relatively quickly. B2s2 should hover...
IMHO it's not mission critical, and many systems don't use it. If you should decide to skip replacing it, I don't think the system would show any difference in operation.
Just to get it out there, make sure the bulbs are correct and not internally shorted. An 1156 jammed into an 1157 socket can cause this type of failure. Similarly, if the bulb is shorted internally, it will cause the same thing.
Is the remix egr on ported vacuum or solenoid control? If ported, the source hose connected to the wrong port may cause this issue.on a similar note, a leaking control solenoid can cause the same thing.
If you don't have emissions inspections, just stick with blocking it off.
My ax5 would do this when the clutch hydraulics were failing. Check the inside of the firewall at the master cylinder for brake fluid running down the wall. (And possibly into your fuse box if it is old enough...lol)