a while back Holley tech told me that 660's come jetted square @ 76 all around, so with PV's in the front you'd start at 68/76
here's where it might get tricky though,
did you check to see that the vacuum reference for the PV's through the base plate into the main body cavity exists?
and with a 1:1 pri/sec throttle ratio, the fat secondaries w/o any PV's are still gonna richen up the midrange- is that why you're jetting the sec's lean?
it might work if you enlarge the PVCR's to flow more full power enrichment fuel?
(power valve channel restriction's) they're the 2 small holes that meter fuel into the main well from the PV's. the power valves don't actually meter fuel, they're just an open/shut vacuum operated valve
there'll be phantoms, there'll be fires on the road... and the white man dancing