All done, took about an hour and a half, nut at back was a real slow job, especially difficult to put back without dropping it! Not for the beginner, but do-able with a good selection of tools. Pleased to say leak has stopped, and alternator is still working - touch wood.
Lexus in Bristol quoted me £98 including vat and oils to do this, which is a reduced rate for owners of "old Lexus' - to stop people getting their Lexus fixed by other garages " Well woth investigating.
I tried the power steering fliud flush, found elsewhere on the site, which involves 'blipping' the engine with the key whilst a hose from the return pipe sends old fluid into a bucket, and my engine hated it. Started spinning uncontrollably even with the key in the off position, so be I must say I can't recommend this procedure, it scared the life out of me!!. If you need to change the fluid, which we all probably do, do it properly.
Easy job except for the rear bolt!!!