I would first run a piece of string down the center of the tips, end to end to measure how much it needs to move to make it straight. At the curved end tip, you will need to hold the string where you feel it should be to make it straight, and measure that distance. Then determine where the bend/curve starts and clamp it at the riser side of that point in a padded vice with the curve pointed upwards. Then hang a gallon jug of water on the end of the limb tip from the string groove. Then take a metal tape measure balanced on the floor and run it from the floor up to the bottom side of the limb. Leave a gap between the bottom of the bow limb and the end of the tape the distance you need it to move, plus about 1/16th more. Apply heat with a heat gun to the belly side, right at the end of the vice where your curve starts, keep the heat gun about 12 inches from the bow. Then keep an eye on the bow and end of tape measure, in about 5 minutes you should see the bow getting closer to the tape measure. When it almost touches the end ot the tape measure, cut the heat. Let it cool a good half hour, till the wood feels cool. Take the weight off and then check it.
OR, bring it over to my shop this Sunday or any night this week and I will help you.. Piece of cake Alan:)