After reading your post, I took a peak at alldata to look at engine configuration. Firing order, intake manifold layouts ( upper and lower ), cylinder numbering and so on. #1 and #4 cylinders are both front cylinders left and right banks , they share a common intake runner and fire one right after another. with the info posted here without you posting some wave forms to look at, my best three guesses would be - big vacuum leak at front of manifold, tight valve adjustments ( this is a solid lifter cam ), burnt or leaking valves caused by different reasons, and possibly worn cam lobe or lobes. If you have a WPS500 pressure transducer you should post running and cranking cylinder pressure waveforms of both dead cylinders and ones of a good running cylinder to compare them to. Posting one of the WPS500 hooked up to the intake vacuum at cranking might be helpful also.
Jim just south of ya in Florida.