Which differential for a scratchbuild?

[Three Peaks]

The uprights are the part that hold the brake calipers, rotors, and hubs/bearings and connect to the control arms. You'll need them to position your parts, build your control arms and pick up points, and measure the lengths of your axles so you can have them shortened, along with deciding what backspace of wheels you will need or want, where to position your trailing link, and where your shock mounts will be located. They are kind of important at this stage of the build IMO.

As for mounting the differential, I used a 2 x 3 rectangular tube coped to fit the round chassis tubes on each end at the correct height for the differential flange to be located. You need to determine the center line of the axles from the center line of the wheels with the frame at ride height. There will be a lot that will go into this stage of the build compared to the rest of the scratch build. There aren't a lot of blueprints to help you with this part of the build or the uprights you will probably need to build to fit the Tbird/Explorer IRS uprights. You can use original style uprights and adapt them to your differential if you have the ingenuity and ambition. Or, you can get the Jag/Dana 44 type rear and use the same system Kirkham uses with adapters to the stub axles and Porsche 930 axles to go with their machined uprights. Pretty expensive option but plug and play.

Sounds like a fun project. Post pics as you go along- BTW, how far along are you at the moment?

Bob