There was an .0023" - OS adjusting screw available for service- C2AZ 6549-A (7/16in -20 X 1.40in).

Doubt that you will find them NOS but have to be available quality aftermarket (TRW).

BTW- The 1.54 ratio rocker arm was later replaced (FORD Service Replacement) by the 1.43" rocker arm and that is probably why you see mixed parts on engines.

TED EATON has an excellent TECH ARTICLE on valve-train geometry. It would be a good idea (IMO) to read and check for after any service repair/modification.

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The question was if I would be able to use the lock nut type adjuster in the rocker that came with an interference adjuster. I tried it and the lock nut adjuster felt the same in the threads that came with interference adjusters as it did in the original rocker. I had to remove the interference adjusters from the rockers I used on the new shaft to clean the sludged-up oil hole to the push rod. Those interference adjusters must be intended for one-time use because they didn't take as much force to reinstall them as it did to take them out. 

Re read your post & answers & am somewhat confused as to what you need to do? However, one thing for certain is; the one piece interferience style adjusters will not work as a replacement in the earlier 2 pce adjuster rocker arms, due to the interferience fit thread..


Paul

Thanks 57RancheroJim, That is very helpful. I found this on Y-block technical: 
EAN rocker is 1954-1955 1.43:1 ratio
5751066 is 1958 - 1964 1.43:1  ratio
1.54:1 HIGH RATIO ROCKERS ARE ECG 6564
The rockers that are in the car now are EAN and a 1/4" drill will almost go in the gap. My replacement rockers are 5751066 and a 11/32" bit will almost go in the gap. But according to the above information, they are both 1.47 ratio. 

I find that a long-handled wrench provides for more precise adjusting than a screwdriver. Also, why not utilize the best of both worlds? Interference/hex-head screws PLUS a lock nut works for me.

6 VOLTS/POS. GRD. NW INDIANA

Don't forget Y's over the years had two different ratio rockers and you don't want to mix them. heres how to check.

thanks, I'll look at that area.

IIRC, and it’s been almost 50 years, the “interference” is in the thread in the rocker, not the screw. If the top of the rocker is machined so the nut can properly tighten, it should be ok. As to length, it’s been too many years, I can’t comment.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

I want to put the nut-type adjuster in the rocker that had interference fit adjusters to keep them all the same. Will that be a problem?
I have a completer set of the interference type and can install all of them in the rockers that now have nut-type adjusters if it will work better. 

If you look closely, the threaded portions of the rockers where the adjuster goes are different lengths.  The rocker with the nut is longer and using a interference fit adjuster may not have enough length to get the correct gap.  I ran into this, but the length was just enough.


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