oil filter plate 340

When you do this, you also need to examine the retaining bolt/adapter, to make sure it has a matching cross-section, else it's a waste of time.
as @Oldmanmopar states, the plate will lose tension, and mine would no longer support 10W40 when cold.
My solution was to install a second plate, similarly drilled and indexed together. Do not use the retaining "bolt" with the internal 3/8ths drive; it is too small. Use the one shown in Post #2, with the external hex-drive.
If you intend to spin over 6000, you need to do the additional oiling mods detailed in the How-To section, to protect your rodbearings; and you should really include a larger capacity oilpan, with a larger-diameter pick-up tube.
if you intend to spin over 7000, you need to connect the lifter galleys as described in the article. A deep pan should be mandatory, and your oiling system should include porting work.
And most importantly, you gotta keep the pan full of oil. At three quarts in the stock pan, I have lost stock 340 cranks at modest rpms . In my street-only car, I now run 10W30 in a Seven quart Milodon Roadrace pan, but with just Six quarts in it, to keep the windage off the crank. It seems to be working as the engine now has over 100,000 miles on it, with no issues..