Help? - Autoguiding for film photography

I wonder if someone with astrophotography expierence can answer a question for me? I am fairly new (last couple yrs) to film astrophotography with a permanent pier mounted LX200 10" f10 scope. I am doing film photography with a OM-1 camera attatched to the LX200. Most of my interest in photos is in deep sky objects (galaxies, nebula, ect.) I am tired of trying to guide on stars too dim visually with a guiding eyepiece and my off axis guider. Hence i have been looking into several options for autoguiding. Is losmandy rings and a refractor with a autoguider the best option? If so what size of refractor would be recommended with both optical and mechanical considerations? Or should i stick with a autoguider on my existing offaxis guider? Also i noticed on Sbigs internet site, a new product, called the FR237 which acts as a small guidescope with thier autoguiders. This option seems to be less in size and wieght, i would think a good thing. But does it work well enough to a first timer to invest into? How about using the existing 8x50 finder scope with its dovetailed holder, and a little machining adapter and a CCD autoguider? (the eyepiece unscrews off the back of the 8x50 guidescope) Would that accomplish the same as a FR237 mounted to the front of a autoguider? All of these options would take a bite out of my budget. So if someone could give me practical answers and expierences on what they found works and doesnt, before i invest. I have to do something different than visual guiding?
Thanks

Anthony,
Well, I have just started to get into prime focus astrophotography (been doing piggy back for a little over a year now) and here is what I have found. Just about every article that I have read says not to guide an SCT with a guide scope do to flexure in the system. Your best bet is to continue doing what you are doing with the OAG. That being said, I am using Lumicons Giant easy Guider (For my 12" LX200), which has a built in focal reducer. This focal reduscer can be placed in 2 spots. it's normal spot is between the pickoff prisim and the camera mount, which means you will still be guiding at f/10, but shooting at f/7.5. The other position at which you can place the FR is between the pickoff prisim and the ota, with gives you an f/5.5 system for both guiding and photography, but will introduce some vignetting into you photos (Which can be cropped out). I have been guiding with the ST-4 both at f/10 and just last week, at f/7.5...the GEG made a huge difference.
Here is a link to Philip Perkins site for guiding an SCT...Very helpful..
http://www.astrocruise.com/guide.htm

I hope this helps.
Don Spencer