I started this thread, and appreciate all the advice. Here is a little summary of my thoughts and a few photos after I succesfully finished this project and am now receiving CCTV (95W, Galaxy 3C) on my 18" dish.
Although there are plenty of threads on this site warning that you can't get 'real' FTA on anything less than a 30" dish, there are also several others that state that is it possible. I read through these and then I started this thread with the hopes of getting some clarification on doing this myself, and as you can see above I received some great advice.
With the old directv phase I dish on my roof and 2 cables running from inside the house to the dish, I would only need to replace the directv lnbf & bracket with a linear lnbf & bracket, and aquire a receiver.
I bought the following:
receiver: Coolsat 5000 off ebay ($41 shipped,
http://www.satelliteguys.us/fta-mpeg2-equipment-reviews/48118-coolsat-5000-a.html)
lnbf ($34 shipped,
http://www.satelliteguys.us/fta-mpeg2-equipment-reviews/57129-sadoun-standard-dual-lnb-4-a.html)
lnbf bracket ($7.50 shipped,
Accessories-FTA Satellite Equipment)
I considered the newer, cheaper ($19 shipped) Techsat Tracker II+ single output LNBF (
http://www.satelliteguys.us/fta-mpeg2-equipment-reviews/116168-techsat-tracker-ii-0-2db-lnb.html) which has a lower noise figure mentioned above in link from Anole instead of the sadoun, but since I have the 2 cables already running to the dish and I might want to add another room later, I went with the dual. Plus, the sadoun is warrantied for 2 yrs vs 1 yr on the techsat, so hopefully that extra $15 is worth it.
I also could have rigged a bracket, but I'm generally not that handy, so it cost me another $6 over the above mentioned conduit hanger method. This bracket also has the skew scale molded in, so I thought that would help a newbie like me, given the importance of skew esp. on smaller dishes.
So overall I spent ~$83.00, could have gotten by on $62 (or less if I looked harder for a less expensive receiver). Anyway, I didn't have to buy a dish and install it so I'm happy. No duct tape, wood or hose clamps required...
I used the focal point template that Anole posted, removed the old lnbf, installed the new one with the proper skew (I needed to drill a hole to properly position the lnbf). I messed around aiming the dish for almost an hour before I was receiving a signal on 95 (G3)-11780 H 20760 (
http://www.satelliteguys.us/free-air-fta-discussion/85225-i-need-strong-transponder-aim-my-dish.html).
Signal quality moves between 66-67%, which as I understand from other posts is close to the minimum necessary to get a picture. That's ok, the picture is beautiful, and I can fine tune it again if necessary.
Thank you to everyone who posted in this thread and thanks to this site in general for the archive of information.
: I know others have done this so my project is not cutting edge but I have this working now to my satisfaction and appreciate the help offered.
Maybe I will get bitten by the FTA bug and need to expand later, but for now, CCTV on my 18" dish satisfys me.
Attached are some photos for the archive...