I would suggest looking over at the 335 forum...
Ford 335 "Cleveland" Series Engine Forum
As far as the rebuild goes on the block...I would suggest having the lifter bores bushed with restrictor inserts to solve to top end oiling problems.
The things I have found by reading and talking with the gentleman from MME {one of the top guys in the Engine Masters challenge}.
I am no expert but using the stock crank and good rods and pistons 350-400 hp is more than do-able.
The oil pump thing has been debated alot, but the moroso spring kit on a melling standard volume pump, and call it a day.
I need to honestly read up more on the cylinder heads, I have a '70 2 barrel engine in my 72 torino right now, and I want to rebuilt the 72 CJ engine original to the car but get new heads, like from CHI, some of their 4V heads would seem to fit the bill.
that's my 2 cents, IMHO.
Have a good one.