Here's a pic of a Saginaw that I faceplated 3rd gear using Liberty Faceplate parts made for a TKO. Basically, split one side of the TKO slider off using a die grinder attached to my lathe's tool holder with a thin cutoff wheel, then welded that onto the Saginaw slider...
Here's a pic of a Toploader 1/2 slider that i added TKO faceplate parts to 2nd gear using the same method. This pic shows the parted off TKO slider piece sitting on top of the Toploader slider...
Here's a pic of the two parts after they were welded together, after I removed the TKO's inner teeth...
Here's a pic of some Liberty TKO parts before they were modified...
I would imagine you could use some Gforce .5 degree parts to do the same, but you would need some pretty robust shift forks/rails/etc if you plan to jerk your transaxle into the next gear like a G101A without using the clutch pedal.
Grant