Anyone live near Northern KY that could assist?

Hi, I live in Northern Kentucky and I have a 78 bronco with a 72 Lincoln 460. It has a tick coming from the passenger side that Started out as something minor, but I've made it louder after I messed with the valves.
Problem is, I can't tell which valve it's coming from. I've never had an issue finding a ticking valve/lifter before, but I can't find this one. I've used a stethoscope, a wooden broom handle, put pressure on each rocker to see if it changed, checked the exhaust header for leaks and hot lashed each valve. No dice. I had this thing running like a top, crazy power and now it's just sitting there ticking away.
It's a bummer, because I've done a lot of work to it to get it ready for the trail, I even painted it just for the hell of it.
But, if anyone here lives near me that could help, I'd greatly appreciate it.