Re: T18 parts
The ford countershaft is the same as the jeep countershaft, aslong as it is the same ratio (close or wide). The ford case is different from the jeep case, to use it you will need to overcome two problems: 1 the rear face of the ford case will need to have the existing bolt holes plugged and new holes drilled to mate with your dana 20 adapter plate. 2 the ford case has no provision for a rear mount, you will need to figure out a different method of attatching the rear transmission mount.
good luck, jjc