Using lead to fill trim holes

I've done it before but it was a long time ago (like 30 years). I don't know how accurate my recollection is but I seem to remember trying to get the heat correct on the panels to control the flow of the lead being one of the key factors. Too hot and the lead would run, too cool and you wouldn't get adhesion. If I remember, I was using 90/10. Make sure you have your tray of wax handy for your wood paddle.