I was surprised when I chkd specs on springs that the Lunati dbl 73949 has a smaller od(1.440) then comp 901(1.494). But I'm assuming the double doesn't need to be as wide due to dual springs?
We never even thought to chk rocker arm clearance when we did the 273 in 2012 and it has the wider comp 901 springs.
Hope you make some progress soon.
I wonder if Mancinis rocker arm sets give a little more clearance?