The Ultra IBEC will drop receiver buss voltage down to the point where it's safe for the ignition module. 5.3 volts is the number that comes to mind. I bought mine through Syssa, though I know you can get it elsewhere as well. To my knowledge the Ultra has a pretty good reputation.

I understand the Rcxel will do that also, but there's some work that you'll need to do to it to make it do that. Doesn't look like too big a deal to me, but I haven't done it yet. Haven't seen many comments form those that have, so how well it works is kind of an unknown at this point.