Cnc router help

I just in the way to buy my own cnc router.
For now I have all pillow block sb16
step moto 34
motor driver
controler board
I wish 3x4x8' axis.
I'm in process to order ballscrew precision and rod Thomson.
the question I have is to have suggest about the right length

For now I thought order
Length diameter lead Accuracy

36" .75" diam .200 0.003 / 12" unmachined
66" .75" diam .200 0.003 / 12" unmachined
96" .75" diam .200 0.003 / 12" unmachined

All 1" diam thomson case 60 rod etc...

8' of pre-drilled rod and 8' of aluminum extrusion pre-drilled
Two times
All 1" diam thomson case 60 rod etc...


66" of pre-drilled rod and 66"of aluminum extrusion pre-drilled (hole
fit together)
One times
All 1" diam thomson case 60 rod etc...


66" linear rod not predrilled
Two times
All 1" diam thomson case 60 rod etc...


And the first item from ebay #534560387
You remember 36" not predrilled linear rod fro 33$
Two times
All 1" diam thomson case 60 rod etc...

Someone can correct me if it appear too excessive or too short.
Ans specially for the ball screw diameter, I considered it was more
simple like that identical diam.

And by this way I will have need friendly metal shop service for my
perfect right angle and hole???


Thank

Wilfrid