Your timing cover appears to have a factory hole for a dipstick so you could use any dipstick and matching tube that fits it--stock 289/302 or 351w stuff will all work. The oil level should be the same irregardless of pan capacity. I use a 289 cover on my 351w block with Canton 7qt pan and the dipstick assembly is aftermarket chrome stuff for a 289.
Hmmm... Bliss? Green? Or? While I do my own assembly anyway, this is a busy time of year for them, and typically a 3-4 week wait for machining, or 6-12 weeks for an assembled engine. I paint mine too.... There is a waiting list to have this guy do your motor so I opted to paint my own block.
Dave at Flow Technics? LOL - doesn't matter. Anyone with a production shop and halfway decent skills has a waiting list these days. Good for them. :tup:... but has drag raced for 50+ years even owns his own super flo bench...lol