New member, first post!  This is a great forum and I plan to use it frequently on my first major restoration project.  I have a 56 Crown Victoria, Raven Black, with M code 292 and Fordomatic transmission.  The car is now nearly completely disassembled and ready to begin frame-off restoration. My Dad purchased the car used in 1958 and has been in our family ever since.  While it has been garaged nearly the entire time, it has neither been started nor driven in over 25 years.  I am starting my list of purchase items for upcoming swap meets and online shopping and want to confirm what I am starting with in the engine and get suggestions for budget upgrades.  I plan to keep the 292 and don't need a hot rod or race car.  It will not be a daily driver but will only be driven on fair weather weekend cruising and to area car shows.  I want something the starts and runs reliably, decent gas mileage and little maintenance/tuning.  So to start I have a few questions:
1)  Engine block - The casting numbers are EDB 6015 A.  I understand this to be a 55-57 Dearborn 292. Is that correct?  I do know that this is a rebuilt engine and not the original engine to the car.  There is an aluminum plate attached to the side of the engine with 3 different overbore numbers.  See attached pic.  Numbers are in the following sequence: 040, 020, 030.  I would have expected one of them to be marked in some way to indicate the cylinder overbore for the rebuild, but can't see any marking.  Do these 3 numbers all indicate something on this tag?  
2)  Carburetor - The intake manifold appears to be the standard 56 4bbl intake with casting numbers ECZ-9425-A.  It has the original Holley "teapot" 4bbl carb.  As long as I can remember, we always had issues with the carb despite a few rebuilds.  I would like to upgrade to a later model 390-450 cfm carb.  I realize that I will either need to find an "ECZ-B" intake (which are difficult to find and expensive), or use an adapter plate (such as Trans-dapt) to attach the larger bore carb to the smaller stock intake.  Are there any issues with using these adapters and are there any suggestions on good street carb to use for my engine?
3) Ignition - The engine still has the original Loadomatic distributor which I know I will need to replace if I change the carb.  I would like to go to electronic ignition.  As with the intake, the 57 and later distributors appear to be difficult to find and expensive.  It also sounds like I should avoid the rebuilt Cardone y-block distributors based on info from this forum.  Has anyone used the Pertronix D135700 distributor made specifically for the y-block?  Would this work for my 56 292?  Or what about all those billet electronic distributors (Maxx performance, CRT performance) for y-blocks that you see on ebay for $200.  Has anyone ever used one of these or are they cheap import junk?  

Any other suggestions for a budget 292 upgrade would be greatly appreciated.   Thanks!