SW20 Solid State Relay Power Steering Issues

Hi All,
 
I have a 91 mr2 with 94 gen 3 3sgte running gear (engine, gearbox, ecu, wiring harness up to kick panel).
 
Ever since I bought the car with the old N/A gear, the power steering light has come up on the dash however Power Steering worked fine. After the swap it continued to work fine for a while until it eventually started working intermittently.
 
The key trick worked for a while, however eventually stopped working at all. I have checked the speed cancelling sensor on the steering wheel which seems to be fine (as per bgb diagnosis), have given the pump direct power to which it turns on, have tried 2 oem relays which both clicked, also tried replacing power steering ecus with ones known to be working, topped up fluid with genuine toyota products however I still had the same problem. When bridging terminals Tc and E1, my power steering light will continuously blink twice every second, indicating no malfunction.
 
I recently replaced my relay with a 100 amp solid state relay as recommended by some users.
Finally, this seemed to have done the trick !
First time since owning the car, no power steering CEL!
 
However, i noticed when leaving work today as I started the car and warmed it up, it was all good no CEL.
As i started to drive for a while, I noticed the CEL had come back on and low and behold, no power steering.
 
I got home, checked the SSR which seemed to be fine (LED still lit). When i turn it on and off it will work, however didn't expect to have this problem with the SSR. Frustrating to say the least, thought I had finally gotten a 100% fix.
 
Does this indicate my pump bushes are worn and perhaps is on it's way out?
 
Any help would be much appreciated.
 
Thanks & Regards,
Abs

I did not.
I merely replaced the original relay with the SSR.

How would I go about installing a flyback diode?

I didn't install a flyback diode either when I changed to a SSR, because I assumed that it's already there, maybe in the motor itself.

New power steering brushes are expensive last i looked. The brushes in the pump are an easy task to tick off as trouble shooting. They are the four big black bolts around the pump. Do one at a time, remove delecately, end of the spring attached to the inside of the bolt is a metal end. Rub the metal end with some 180-240 grit sand paper on the end of your finger, gentle sanding passes on the face. The action is best described as how you would clean the surface of a distributor points (in the old days). Keep the concaved shape, just clean the brush surface and flatten any lumps. Reinstall and see if it solves it.