wheel lug studs for pl411 rear drum brakes OR conversion to disk brakes on rear of same car

[Chief]

Broken wheel lug studs on my pl411...  happened and wheel decided to pass me on the way down the road.  I am looking for lug studs for this sweet little thang, can't find them anywhere and have no idea size.  m12 is far too large.. m10 is far to small.  IDK of an m11.  What are these things, anyway?

 

If not, has anyone done a fabrication and install of disk brakes for the rear of this car?   I'm thinking that Honda disks might well fit.. bolt circle is 4 lug 100mm as opposed to 113.x like original but easy to work with using wheels with two lug patterns/sizes.  It looks like i could fabricate caliper mounts, install the disks and go merrily down the road.  

 

Thoughts my friends?  This was my wife's first purchased car way back in 1972.. J13 four speed, completely redone inside except for the glove box bucket (haven't figured out how to make one yet... maybe fiberglass?) and haven't butchered with seatbelts yet.  Still need window rubbers on the doors all around (4 door) handle retainers and trim.. 3 tiny spots of light rust and the ws wipers don't yet.  Cherry red and needs a new radiator but the old doesn't leak so likely just recore. 

 

new to forum but ancient in years.

[bananahamuck]

They aren't metric they are SAE 

 

7/16ths X 20 

 

most common on early 70s Chevy cars ,, Nova- Chevelle cars like that.  Probably TONS more but i don't know. 

[Rotarded]

610-157 is the part number I just bought at Oreillys for the longer 7/16-20 studs that worked in my 521.

[Chief]

Great!! Thank you both!  

OMG - i was driving myself insane because i assumed they were METRIC~!!!

[iceman510]

7/16ths-20 is so dimensionally close to an 11mmx1.25 that it is really hard to tell them apart.

Edited Friday at 05:35 PM by iceman510