Hi grandmax2, welcome.
I can't say what you should do, but I can relay some information that (like you said) is buried withiin this forum, that may help you decide.
You quitting Lyrica too?
If you decide to stay cold turkey, please understand that it could be a rough go.
The step from 120 mg to zero is steep, and if you are one of the unfortunate ones that will suffer side-effects, they will begin in earnest in a day or two, and could be very powerful. They could be very strong for 3 to 4 weeks or longer, then taper off to more tolerable levels over the next few months, and within a year you should be pretty much back to normal. If you are working, it would be wise to take a few weeks off at the beginning.
I don't know what the interaction of Lyrica would be if you're quitting it at the same time. How about just do the Cymbalta, then consider weaning off the Lyrica at a later date?
Advise your physician, as you may need some follow-up.
Should you elect to withdraw slowly, do it without steps: make the withdrawal in a linear fashion, reducing the amount by the same increment each day. For example you might reduce by 1% per day over 100 days. Day one take out 1% of the beads; day two take out 2% of the beads; day 3 take out 3% of the beads and so on to day 100. Should you encounter some rough days with strong symptoms, you might want to stay at that dosage for a few days until things stabilize- you may want to add a few beads back for a few days. Listen to your body.
The withdrawal side-effects are diminished by tapering off like this, but you can anticipate some uncomfortable days. There is some anecdotal evidence that suggests your brain will heal more satisfactorily by slow-tapering rather than going cold turkey.
The choice is yours. Should you go cold turkey and encounter unbearable side-effects, you can go back on the drug at your last dosage and stay there until you stabilize before beginning to taper off.
NOTE: The manufacturer (Eli Lilly) recommends a slow tapered withdrawal, and DOES NOT recommend cold turkey.
You can do this. Have someone who you can call. Stay healthy. Walk. Drink lots of water. And go slow.
Best wishes on this journey!