Hi there. Did you find the sources of your vacuum leaks? I had an airbox on mine so it was easier to chase them using a smoke tester. Amazing how many leaks you will find when you think everything is sealed properly. All is properly sealed now, i had to use sealer in some placed that i didnt think would ever leak but before i chased them all i noticed that as the engine got warmer, the worse the leaks got, so the revs rose even higher.
Following your thread, i've not put any idle air control on mine, would be nice to have. At present i have to feather the gas pedal for about 40 seconds and it usually all settles down pretty quickly after that.