I plan on using an oil pan from a truck on a 292 that will go in a Model A and I don't have the dipstick or the dipstick tube. I have mocked up a tube and a stick but don't know where to mark the "full line". I guess I could put 4.5 quarts of oil in and mark the full line at that point but the front of this pan is modified a little and that may change this level a little bit. The other thing I got to thinking about is, are the truck pans 5 qt or 6qt? 
From what I understand, there two different truck pans, one heavy duty truck and a pick-up pan. Both of these pans are rear sump but the pick-up pan has two "steps" before the slope to the front and the H.D. pan has just one. I have the H.D. pan as mine has just the one step before the slope. Is this H.D. pan a 6 qt pan?
So, I'm thinking the best way to do this is to find out how high the oil should be below the pan mounting surface of the block and mark the dipstick at that point. Does anyone know how far from the block the oil level should be? 

I think you’re making this harder than it has to be? Why not put 5 quarts in and mark the dipstick, add another quart and mark the dipstick.

  Dennis in Lititz PA

The truck/pickup and Thunderbird pans are 5 qt + 1 qt for the oil filter.  The HD truck oil pan is 6 qt + 1 qt for the oil filter.  If dealing with a truck rear sump oil pan, be sure it has a baffle in it to control forward slosh or oil movement during braking.

Here’s the link to showing a picture of the three basic rear sump oil pans.
http://forums.y-blocksforever.com/FindPost74375.aspx  

Lorena, Texas (South of Waco)

The way pintoplumber described is the way I have done it.  However, after filling it with the 5 quarts, I run the engine for a short time to fill the filter and oil passages.  Wait an hour or two for the oil to settle and then mark it as the one quart down..  Add the 6th quart, run it gain, and then check level.  This will be your full mark


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Ted, so the H.D. truck pan is 6 qt plus one for the filter making 7 quart total? and the car pans are 5 qt plus one for the filter making 6 qt total? Did I read that right?

You read that right.  The owners’ manuals for the cars actually says 5 qts plus the filter.  I always just figure a quart for the filter so it’s six quarts total for the front sump pans.

Lorena, Texas (South of Waco)

This is a quote from the thread that Ted linked to a few posts ago. I'm now doubting that I have a H.D. truck pan as my pan at the deepest part is right at 6" and the shallow part tapers from 4.5" down to 3.5" . My pan does NOT have the two step taper that the pick-up truck has so I thought it was the H.D. pan. Inside my pan it has the baffle like the one shown in the other thread that is the pick up pan. I guess I could say that my pan "could" be 4 5/8" as that is only 1/8" more than the measurement I got but no way the deepest part is 6 3/8". And I have the baffle is just like the pick up pan not what is in the H.D. pan pictured. With all that said my deepest part is 6" not 5 5/8". 
QUOTE FROM OTHER THREAD:
The center of the most common truck pan, the 5 quart pan is about 4".  The deepest part is about 5 5/8"
The HD 6 quart pan is about 4 5/8" at the center and 6 3/8" at the deepest.

I clipped this from the other thread for reference.
Top one is the H.D. pan middle is pick up pan.

     
This is inside the pans, top photo is the H.D. pan. My pan has a baffle like the center pan( pick up pan) not like the top, H.D. pan. If you can see the bottom of the pan dips down a little at the drain plug a little, maybe this is where the other poster got the 6 3/8" measurement. I'm calling it a 7 Qt pan and moving on with that, 

The easiest way for me to identify the HD oil pans is by looking at the shape of the sump from the outside of the pan.  The pickup pans have what I call a double hump or two different depths at the sump section while the HD pans have the same depth for the length of the sump.  You do see differences on the pan baffles on the pickup and front sump pans depending upon the year model so it stands to reason that the HD pans could have had some variations in baffles also during the various years of production.

Here’s the same picture showing the bottom of the pans but with a highlight on the sumps of the pickup and HD pans.  The HD pan is at the top of the picture and the pickup pan is in the middle.

Lorena, Texas (South of Waco)