Retrofitting a 160 water-oil cooler to your TF ought to be pretty straightforward - all the mounts are already there on the block - and so long as you get all the associated parts, it all ought to be plug and play. Buy second hand - so long as the donor car hasn't suffered from HGF it all should be pretty easy sailing. If the donor car has had an HGF, then ensure that the radiator-in-a-bath is thoroughly flushed of that nasty oily-mayo residue before fitting.
A front-mounted oil cooler is probably the simplest option. But these are not usually thermostatically controlled, and have the additional problem of introducing a lot of 'dead space' in the form of excessively long oil pipes running to and from the front of the car. One solution used by a friend in Mexico was to mount the rad behind the coolant rad, which will certainly effect the efficiency of the oil-cooler rad, but prevented over-cooling the oil (just as bad, potentially worse than too-hot oil), and even in Mexico, he's happy with the results - more here:
http://www.mgf.ultimatemg.com/group2/DI ... /index.htm - and note that this is fitted to a car fitted with air con, but not, I believe, steptronic semi auto CVT gearbox.
The other option is to use a Laminova after market oil/water cooler. This will almost certainly work out more expensive than the MGR kit, but is probably more efficient. An alternative is to use a R25 diesel Laminova oil cooler - but mounting it in the engine bay is very tricky. The best option is probably to mount it up front, which is Jerry's plan I think
http://www.mgf.ultimatemg.com/group2/co ... cooler.htm
). So, I'm thinking about oil coolers 
. I have seen two alternatives:
In addition, you say that the fixing is difficult and expensive 
