Rear axle housing drain plug.

[59meteor]

Yesterday I stripped down the 9" rearend I plan to narrow for my 59 2 door sedan, which supposedly came from a 1958 Edsel "high line", Citation or Corsair, which is wider than the typical 57-59 Ford car housings, and also had 5 x 5" bolt pattern, with the large axle bearings. I figured since this rearend is kinda an oddball, that I would cut up this housing, since my original rearend would be more popular for resale. I will be having the housing narrowed about 3/4" per side shorter than my stock rearend, and ordering new custom 31 spline axles, so I will only be using the housing from the Edsel. The bottom of the housing has a drain plug, with a square hole. I assumed that it would be the same as the diff filler plug, which is removed with a 3/8" drive ratchet and extension, but the drain has a smaller square opening, but larger than a 1/4" drive extension. Do the 57 Ford car housings use this same, uncommon size drain plug, and if so, how do you remove it? I am not familiar with square sockets available in a varity of sizes. Anybody know of some? Otherwise I may just need to grind down an old 3/8" drive extension, and hope the reduced square will remain strong enough to  remove the 60 year old drain plug.

[Hoosier Hurricane]

I use a piece of 5/16" key stock and an adjustable wrench.

[rmk57]

Remove it once and replace it with a regular 3/8" allen pipe plug.

[suede57ford]

I used the end of a steel number punch in the plug.  Fit perfect and was hardened so it came out.  Yes put a modern plug back in it.

[gasman826]

I have a Snap On socket.  Here is a link to S-K:

https://www.ebay.com/itm/SK-PROFESSIONAL-TOOLS-41450-Pipe-Plug-Socket-3-8-Dr-5-16-Square-G5102937/222274482155?epid=1400208059&hash=item33c0976feb:g:pM8AAOSwvApaB7hl:sc:ShippingMethodExpress!49221!US!-1