Stock magnum heads cam roll call!

The stock lifters they used in the crate engines are fine. Instead of changing the lifters, get a custom ground cam to maximize your package, along with your planned intake swap. The crate cam is just lazy because it was made to clear stock head retainer to guide clearance and work with higher stall converters and taller rear gears.
Agreed.. My Howard's grind ,was 229/233 @ 050' advertised was 282/286 ... Slower ramp cams ,work... it takes experience, to learn the difference(s)...
Idles at 11 " of vacuum ,@ 900-950 in gear... If you want more street able, pull the intake duration back , ( torque on the street ) ,or widen the lobe centers ,110-114 .... and some head porting, would be good.
Personal experience, you have done....