Yes, putting the grating in front of a camera lens works nicely as the light from the star is collimated. This way you can get a better resolution compared with putting the grating behind the telescope, but only for bright targets as you say. I wrote the method up for the AAVSO Epsilon Aurigae eclipse outreach project
www.citizensky.org You can see the writeup on my website here.
http://www.threehillsobservatory.co....roscopy_11.htm
At the other end of the resolution scale here is the same object using my LHIRES III Littrow
http://www.threehillsobservatory.co....spectra_40.htm
Interestingly although the LHIRES is now sold commercially, all the drawings and design information are still on the web
http://www.astrosurf.com/thizy/lhires3/index-en.html
Good luck with your spectrograph building
Robin