Well guys and gals, here is an update for you,
have been trawling the internet for a few months now, reading up on lots of things on different websites, and found something that might help others in the future, as you know I want an ECU with the part number 89661-50250 but have been unable to locate one a write up I was reading said something about an ECU they had tried on a car conversion using a 1995 LS 400 engine, they tried ECU 89661- 50380, I found a guy on Ebay selling one in the United Arab Emirates, so asked him to open it up and take pictures of the layout of the capacitors and board,
He did, and emailed them to me, I then compared the layout to mine, it had 9 caps in exactly the same position as mine, then I compared other components and apart from a couple of extras on his they were identical, so I purchased it for $40, it came today and I eagerly fitted it, I turned the ignition on and let it load and off again for a moment then prayed it would start as I turned the key all the way, it started straight away, so I let her warm up for ten minutes and took her for a test drive, everything works great I am over the moon no warning lights goes like the clappers and glides like a dream.
I have also found a Japanese import ECU 89661-50241 in America it had photos of the internals of the ECU and again had 9 caps and exactly the same layout as 50380.
I have purchased it, and am waiting delivery, so again will update you if it works or not.
Just thought the information may help someone else in the future, as I was getting to the point where I thought I would have to break my lovely Lexus and now I dont,
Conclusion
Needed ECU 89661-50250 the correct one for the car
Used to get by on ECU 89661-50221 ( good for just cruising around with engine light on) only 6 caps on this one but car was running fine
Working completely ECU 89661-50380
To be tested ECU 89661-50241 and will update you on the results
Also bear in mind My LS400 has no alarm I had to have it bypassed to start the car when purchasing, the guy who owned it passed away and it stood for 3 years in his garage.
hope this helps someone else, as gives you more options
Kind regards all
Phil