I received a p'sak from my rav earlier today permitting me to revert my pronunciation from a modern Israeli-American pronunciation that I learned as a child to the old Yekkish Ashkenazis (with the חולם pronounced as as German au [aʊ] and ע as ng [ŋ], as well as the usual Ashkenazi features). However, while I was davening Minchoh, I noticed that some of my former liturgical pronunciation was slipping through.
Does anyone have any suggestions for how to drill oneself to successfully change the pronunciation for one's Hebrew? (although only partially, I want to maintain the Israeli accent for conversational purposes)