I did this with my DD about a month ago - she was five months then too.
Rather than take it away at night, we started in the morning so when she started to get tired and grizzly, I bounced her in her bouncy chair until she was on the verge of dropping off then put her in the cot. Did this for all of her day naps.
When it came to bedtime, did her bath, massage, feed as normal then just put her in the cot, kissed her good night and left. She grizzled on and off for a few minutes but didn't get as far as proper crying which really surprised me. Sometimes she does cry when I put her down so I cuddle her until she's calm then try again. She's usually asleep in 5-10 mins.
My friend also did this with her lo around the same time. She had one awful night where her dd really did cry for the dummy and she spent a lot of time cuddling her DD until she stopped crying, putting her down then picking her back up if she got upset again. Neither of them got much sleep that night but after that, her dd slept through.
My DD has also been sleeping well since we ditched the dummy - now she knows how to go back to sleep she doesn't need me to help her in the night and we've even been able to reduce and drop her dream feed. As a former poster on 'Sleep is for the weak' (I still read it, recognised your name!) I can tell you getting rid of the dummy was the best thing we could have done.
Good luck! Let us know how you get on.