So with regards to measuring endplay, per some of your notes in other threads:
Checking Forward Hub to Direct Drum end play,
Stack the gear train up to the Direct drum, Place the Forward Hub over the Main Shaft, Hold the forward hub down with your palms & lift the direct drum with your fingers.....The play you feel is the end play. Since I will be using a billet rollerized forward hub from jakes, the end play should be zero for this measurement then?
That is correct!
On a stock setup, that would have end play, where should the endplay measurement be taken and should a feeler gauge or SAE Dial Test Indicator be used?
Reaction Carrier to Center Support looks like endplay should be .008"-.015".
To measure Reaction Carrier to Center Support endplay, I stack the gear train up to the Direct drum, Place the Forward Hub over the Main Shaft, Hold the forward hub down with my palms and lift up the center support to separate it from the Reaction carrier?
I used to do this by feel....But member P10crew built me a (Absolutely Beautiful) fixture for doing it. You just need it stacked to the Center Support.....Hold/Push down on the Center Support & Lift up on the Reaction Carrier.
To measure total rear unit endplay, I just lift up on the output shaft while the transmission is in the holder completely assembled using the SEA dial, correct?
NO.....Assemble the unit up to the Center Support (with the beveled Snap Ring installed).....You
DO NOT need the Reaction Carrier installed for this! Makes it easier/lighter as it does not affect rear endplay.
*You will need to make adjustment here, So the last thing you want to do is assemble the whole trans & have to tear it all the way back down to change a shim.
*Once you get the total rear unit endplay correct.....Then you can fully assemble up the to the Center Support & torque the Center Support hold down bolt.
Parts list that does need to be installed to check rear unit endplay (Top to Bottom).....
*Beveled Snap Ring.
*Center Support.
*Thin (Fretting) Snap Ring.
*Rear Sun Gear to Center Support Bearing.
*Rear Sun Gear.
*Rear Internal Gear to Rear Sun Gear Bearing
AND the factory .041" shim!!!
*Output Carrier (Only to keep everything assembled & center the Sun Gear)
*Output Shaft to Internal Gear Bearing.
*Output Shaft.
*Selectable TH350 Shims.
*TH350 Bearing.
To measure front unit, I flip the trans over completely assembled and lift up on the input shaft?
Input Shaft needs to be pointing straight up, Now.....There
IS free play between the OD Carrier & Input Shaft Snap Ring.
*You will need to lift up on the shaft 'till the Snap Ring barely touches the OD Carrier & ZERO your Dial Indicator.
*However much further the Input Shaft will lift
IS the Front Unit Endplay.
*You're not going to be able to see the Input Shaft Snap Ring.....Got to go by feel!
Total Rear Unit.....003"-.008" (Rollerized)
Reaction Carrier to Center Support......008"-.015"
Direct Drum to Forward Hub......003"-.008" (Rollerized)
Front unit.....005-.008" more/greater than the Rear Unit
Those are correct specs