I am setting up the linkage for the SB 727 on my Gen 3 Hemi. I am starting with a 383 linkage system and going to modify the rod lengths from there. The FSM shows the Transmission Lever all the way forward and the 3/16 alignment rod installed in the bellcrank at the rear of the engine. The picture also shows the carburetor rod pushed all the way forward against the pin. Is that picture the position I want to fabricate all the rod lengths at?

All the way forward on an engine off the choke (off fast idle), and the transmission throttle lever should be held all the way forward too. I would place a spring on it that holds it forward while you develop your linkage. Most hard linkage uses a light spring from the slotted linkage at the carb to pull the whole shebang forward. Later cables use a spring too but down at the trans.
But that's not the whole story - lever ratios are important too - at WOT the throttle pressure lever should be just about all the way back - just before being bottomed out.

There are many different levers so as long as you work towards that end you should be good.

Thanks...

have you looked at the newer style cable PTK from Bouchillon?

it has the same parts as a late model Dak with the spring down low. it comes with an carb adaptor & trans lever for which ever carb you use to get the correct ratio for the trans. (everything from a Dak can be used for replacement parts but the Bouchillon carb adaptor is the key for carb hook ups/ptk ratio)

used for the 82-87 BB conversion kit from Bouchillon.

if you fab from stock rods, yes start out like you stated and build some adjustment into it to fine tune the shift points.

if you have a 3-piece set most time the middle rod is the one to lengthen but with the new hemi the cable may be a better piece to use and get correct ratio on PTK.