T-10 won't align on reinstall

Looking for a 26 tooth T-10 second gear.   Seems the 27 tooth I have now with the 243 counter gears is not allowing the main shaft to mesh so I can't get a straight drive line.   Gears I have with the 243 are input 21, third 24, second 27, and first 34.   The counter shaft is 27-21-19-18.    Just thinking the 26 tooth gear would also bring the 2nd gear ratio to the customary 176 it likely should be.   This is a trannie I've had for years and all the parts came from it so I'm stumped.   Suggestions?  Thanks, Steve

parts can be hard to find, It appears Brian at S&k keeps a lot of amc t10 parts, his number is 631.957.9427. you have to call, its an old school shop with no website. Theres an early style thin flange gear, and a late style thick flange, you will need to mate the correct gear/flange

Thanks for the input .   I certainly seem to need a 26 tooth gear.   When I get one it will still not be an easy swap due to the large snap ring that holds it in place.  

So, where would I purchase the large retaining clip to replace the one I grind off?  

Thanks for information on the difference between second gear sizes as well as tool necessary to remove the gear.   At present the snap ring is VERY scarce so removal and reinstall was/is the best option.  The best tool for snap ring removal is the one like is shown in AMC literature.   When the correct gear was installed, assembly was quick and easy.