Dart 8 1/4 to D60 lots oh stuff to figure out

Please look at my research and tell me if I'm on the right track, when I have it all figured out and the parts in hand I will be taking it to a pro for cutting and welding just want to cut down on cost by having all my ducks in a row snd knowing exactly what I want them to do.

In there = 8 1/4
A)Flange to Flange =51.4
B)leaf center to leaf center =43.02
C)Center line of axle to center of universal joint =11.69

going in =
D 60 30 spline full floating 8 BP 89 3/4 ton dodge pu
A) Flange to Flange =56.5
B) leaf center to leaf center =46.00
C) Center line of axle to center of universal joint =13.47
crkd
D) Axle total width = 60.125
E) Pass axle tube = 18.03125
F) Drivers axle tube = 19.40625
G) Drives axle length= 29.75
H) Pass axle length= 28.375 27.125
I) Total tube length= 37.4375
J) Required bar length= 43.25 ? don't know what bar this is.

Needed parts
A)perches
B)8 3/4 end hubs 10 "Drum brakes or disc conversion BBP
C)Custom length 30 spline BBP axles from Moser or cut,

re-spline and re-drill existing axles which look perfect.
D)Bearings and seals

Cutting & Welding
A)spring perches dropped to bottom and moved 1.4" towards

center with same angle as 8 1/4 Or will I need to

compensate for bigger tubes?
B) flange to flange 5.1 " shorter (will be using 5.5 BS

wheels and have a good 3.5" on both sides so may not need

to shorten?)
B) 1) If I don't shorten the entire axle how do I center

it? Move the perches? Shorten one side?
C)Shorten drive shaft (Anything different with a 904 vs

727? Just swapped in the 904 fresh build with shift kit so

please tell me it's ok!)

So this is what I have so far, please help as I have time

to do this right but I don't want to do it twice, I will

spend money where I have to but am on a tight wife budget.

Cheers!