Here are my videos that document some of the improvements in detail:
Spindle lock upgrade video:    • Spindle lock for my Mini Mill  
Motor upgrade from 250W to 600W brushless video:    • Harbor Freight Mini Mill brushless mo...  
Ring light for the spindle:    • Ring light for the Mini Mill spindle  
Improved locking knobs:    • A small improvement for the mini mill  
Draw bar improvement:    • Quick Tip #1  Mini Mill draw bar imp...  
Installing tachometers:    • Installing tachometers on my machine ...  
Tramming the column:    • Tramming the column on my mini mill  

Links to many of the parts are below, and here's the parts for the cross slide motor:
The motor I used for the for the cross slide is this one: https://amzn.to/3DitFh6
and I used this speed controller: https://amzn.to/3ro8tmY

I have learned a lot from YouTube especially from Quinn of Blondihacks:
   / @blondihacks  
She has an excellent series of tutorials for beginners and demonstrates many clever tools and techniques.

Little Machine Shop for belt drive, column support and much more:
www.littlemachineshop.com
this is the primary go to site for small machine tools and accessories.

Touch DRO: www.touchdro.com

Magnetic Scale four DRO (1m length that you can cut down for X, Y, and Z axes):
https://littlemachineshop.com/product...

My machining play list:
   • Machining  

I am an electrical engineer, so I hand built the start/stop switch with the big green and red buttons (they are actually video arcade game buttons!). But if you search on: "power tool start stop switch" you will find many options for around $10.

Please consider supporting me on Patreon:
  / guymarsden  

Tools I own, use in my videos and recommend (as an Amazon Affiliate, I earn from qualifying purchases.)

3pcs 3/8"/10mm Shank Indexable Carbide Lathe Turning Tools Insert Holder Bit Set: https://amzn.to/3CS95nK
5Pcs 3/8" Inch Indexable Carbide Insert cutters with TCMT110204 Carbide Inserts: https://amzn.to/3WeZmyW
1/2" Carbide Square End Mill 4 flute:https://amzn.to/3H6G36v
ROUND BAR CENTER FINDER: https://amzn.to/3kg3t09
2" diameter Indexable End Mill with 3 Tpg32 Carbide Inserts, 3/4" Straight Shank: https://amzn.to/3GNLbuH
Ball Turning Attachment For 7 x 14 / 7x16 Mini Lathe: https://amzn.to/3ZDscf3
2" Boring Head R8 Shank 1/2" Carbide Boring Bar Set: https://amzn.to/3J1wGpQ
Keyless 1/32" 5/8" Drill Chuck with R8 Shank Adapter: https://amzn.to/3CTUetb
3 Spring Caliper set 8" / 200mm Inside/Outside/Divider: https://amzn.to/3H79nts
Sewing Machine Light LED Light with flex gooseneck: https://amzn.to/3XyhHrv
Deburring Wheel, Nylon Fiber Buffing Polishing Wheel 6 inch 9P Hardness: https://amzn.to/3XlIzLN
Thrust Needle Roller Bearing with Two Washers 1/2" (for mill spindle nut): https://amzn.to/3CS65bg
Metric M42 8% Cobalt Twist Drill Bits Set for Stainless Steel and Hard Metal (1mm10mm/19pcs): https://amzn.to/3HjquIV
Shars DRO for minilathe Zaxis (carriage) position. (You can cut down the 24" capacitive scale it's aluminum.): https://amzn.to/3fjOfFw
Digital tachometer: https://amzn.to/3UePGUg
FLEXBAR Optical Center Punch: https://amzn.to/3WRwpKD
IRWIN Step Drill Bit Set (I highly recommend Irwin brand step drills. They were the originator of this concept in the 1980s and the knockoffs are not nearly as good) : https://amzn.to/3hv4zno
Angel Eye Ring Light (for mini mill): https://amzn.to/3fp5hSy
DC motor speed controller (for mill table feed and minilathe carriage): https://amzn.to/3WOhOjk