Thanks- I'd heard about ammonia way back in my free flight days 30yrs ago, seems people then thought it helped form balsa when soaked in a mix of ammonia/water. I am partial to a method which will be long lasting. The bow isn't centered in the middle of the stab, and I'm afraid that heating the covering alone while holding opposite bend will not be a long term fix, especially once it sets in the sun a few hours. Injecting warm water sounds like it might work, along with some heat during the "re-cure." Thanks for all the ideas!