Thanks for the input and advice appreciated.
After researching as best I could (including YouTube videos of people stealing the Catalytic converter in 60 seconds in broad daylight!)
It appears the choices are:
1. Cat Lock, ( plate anchored to the vehicle chassis protecting the catalytic converter )
2. Cat Clamp: (stainless steel brackets and wire fitted to the catalytic converter and anchored to the underside of the vehicle)
3. Installation of tilt alarm.
Upon further research, it appears the
1: Toyota supplied Cat Lock has failed to prevent theft of a catalytic converter in at least one instance, and after speaking to a garage with a lot of experience in effective catalytic converter theft protection "most of our customers come after they've had their catalytic converter stolen for the first time" ( CarMax Ltd, tel: 02036747100 ) let's just say they were not impressed with the Toyota supplied Cat Lock and believed it would be easy for a thief to circumvent.
2: it appears ( again explained by Carmax to me) most Cat Clamps do not prevent a thief from accessing the bolts required to remove the catalytic converter, assuming they have overcome the actual clamp.
So yesterday I travelled to London, to CarMax Ltd, tel: 02036747100 while they fitted their version of the Cat Clamp, ( my catalytic converter - and removal bolts ) now have an amazing array of stainless steel cabling securing the catalytic converter to the car. In addition, they fitted their own custom designed Cat Lock plate, I inspected the work, and I'm very satisfied.
I paid £225.00 for all labour and parts used including VAT
The garage claim they have fitted over 100 of these, and subsequently not had a single customer lose their catalytic converter.
The garage also advised it would take a thief considerable time to remove the combined protection, suggested well over an hour! I am mechanically competent, and after inspecting the work carried out I agree. (Better than the current 60 seconds!) Remember the reason they are target in the first place is mostly because of how easily are to remove, once it gets considerably more difficult, complicated and time-consuming it increases the risk to the thief, and decreases the risk to the owner.
( PS: while I was there I had a good chat with another customer whose had his car for only a week and thieves had stolen the catalytic converter, he was gutted. The garage were replacing his cat, and fitting the above security)
3: finally the tilt alarm, as we all know everybody ignores alarms, they have become a social nuisance. However I think there is still merit in having one fitted, especially if the vehicle is kept at home. So I shall go to my local Toyota dealer I believe I can have one properly fitted by them for around £250.
if some scumbag thief is prepared to jack my car up, bring all the tools required, make one heck of a din while they try and cut, spend an hour and 1/2 in the process, then they are welcome to my cat, they have earned it!
In the meantime, I will drive, park, and sleep without worrying at all.
And just in case anyone is wondering about, CARMAX Ltd, other than travelling hundred and 30 miles to their garage yesterday and having the above work undertaken, I am not connected, nor received any incentive to highlight the great work they have done. We should also give credit where credit is due. Good honest people, working hard, good service, I highly recommend them.