I've got distributor out of engine on a 57 y-block 292 and I'm driving oil pump with socket and drill while valve covers are removed. I'm not seeing oilflow to either valve train. I know the oil filter was not filled at the start because I did oil change recently, but I kept it spinning for awhile. I also rotated crank in 30deg increments (cam in 15deg incr) and still did not see flow, on the off-chance that camshaft had cross-drilled holes. I assume the head channels are clogged and I'll need to remove and clean them. How can I do further test to know oil pump even works before I remove the heads? I don't have oil pressure gauge, though I suppose I could put pipe-mount gauge on 1 of 4x 1/4" ports along drivers side of engine, probably the one to the left of the oil filter. Does that sound like a solid plan? Are there other easy ways, maybe just open that same port and see if oil pumps out while drilling? I have no idea how oil pressure changes with drill rpm. Has anybody else gone thru some similar exercise that has advice? Thanks.

Further info as follows.  I'm spinning it CCW like the intended distributor direction for 57 y-block 292. Using Ridgid cordless 3/8" right-angle drill, and the right-angle head is getting hot when running it about half-speed. The 4Ah battery is not hot though. The specs for drill are 375 in-lb max torque and max 1900rpm max in high speed mode which I was using. The 1/4" hex socket is in the form of a Destaco 12" long hex bit extension with the quick-change sleeve ground off, no socket needed since extension was already 1/4" hex. This was all I had in-house that could fit into hole above oil pump. The drill definitely felt loaded after initial start of no-load. I felt right-angle head getting hot while using it.  I also made sure that extension thru distributor hole was centered in hole to avoid rubbing on lower hole.  And I pushed down axially slightly to make sure hex extension didn't disengage with pump.

You don’t mention how clean the engine is.  If it shows evidence of sludge, then stopped up or plugged oil galleries is a strong possibility.
 
An oil pressure gauge would help to confirm exactly how much oil pressure you have present, but it does sound like you do have oil pressure.  Once confirming that you have adequate oil pressure, I'll suggest that you try pumping some white lithium grease into each of the oil holes on each head and see if that will clear up the oil passages to the camshaft.  After doing that, then run the oil primer on the engine again and see if you can get that grease to come back up and then maybe some oil flow following that.  If that does not work, then the next option would be to start doing a tear down.  If the engine has been rebuilt in its past, then the cam bearings being meshed into the cam journal is a strong possibility as the newer replacement cam bearings do have softer babbit material.

Lorena, Texas (South of Waco)

Here’s the link to the article that was published in The Y-Block Magazine that went into detail some of the issues with rocker arm oiling on the Ford Y.
 
Y-Block Top End Oiling Woes – Eaton Balancing

Lorena, Texas (South of Waco)

Drill and tap the port in the head to pump the white grease in?

If you have some old Ford Y-Block rocker stands, you can cut one of those in half horizontally and then put a zerk grease fitting in the center hole of the lower half.  That piece of stand can be bolted on the cylinder head and then grease pumped into the galley clear out any potential sludge.

If no old sacrificial rocker stand is available, then any piece of ‘flat’ drilled with the two holes to bolt it to the head and a center hole for a zerk fitting can be used.

Here’s the link to a recent post discussing no oil to just one side of the engine.
http://forums.y-blocksforever.com/FindPost169752.aspx 

Lorena, Texas (South of Waco)

Lorena, Texas (South of Waco)

Im not sure if it would hold enough pressure but a rubber tip from an air gun screwed onto the grease gun or a grommet might work to push grease through. 
Seth

ive never seen both sides fail at the same time.