Well, I can empathise mate. My 164 Cloverleaf 24v went up in flames about three weeks ago due to a massive electrical fault (or so we think). It started as I was moving it in the driveway. Anyway, it was probably the best in the country (no exageration) on a 1995 'M' plate. I won't be settling for less than just under £3,000 from the insurance.
I would say, that if yours is a minter with under 90,000 miles, you should be able to ask between £1,500 and £2,000. If it's clean with higher milage then I'd say £1,300 - £1,500. Nice 164s are really very hard to find now.
Another good place to advertise is Auto Italia magazine. If you buy a copy there's details on how to advertise. It's your direct market and it's free to advertise in there with no word limitation. You could also visit their website www.auto-italia.co.uk
for details. The cars advertised in the magazine get put on there too.
I know it works, because I just bought my replacement 166 3.0 Super via the adverts on the website!
Good luck - it may take time but there's still a market for late 164s in nice condition!