This is a factory non LSD diff. Speedo drive is the blue bit
 

 
This is a factory LSD diff on the left (Yellow speedo drive) and the Quaife on the right. The way the speedo drive clips on and the slightly different diameter means the yellow one cant be used
 

 
Factory LSD left Quaife right
 

 
The LSD bolts. The non threaded part is longer than the non LSD bolts so they cant be interchanged

Do you happen to know the part number for the non-LSD bolts?

90105-12154 for the non LSD bolts. 16 needed

I obtained both speedo rings. The only difference is the thickness of the inner ring component. I think by removing 0.1mm of material from the face of the inner ring it will fit perfectly. I'll post proof of concept when the car is on the road. I prefer the camry speedo ring because it will be perfectly zeroed for 245/45 R 17 rear tyres.