My process and things I learned doing the maximum number and types of mods on an N64 Console.
NOTE: The N64 was made when Lead solder was the standard for all manufactured electronics. Even if the new solder you add is ROHS, the original solder is not.
Mods and their planned order:
Additional Mods (Non-console)
Some of this sequence choice is based on "building" the skills for the more advanced mods, also the state of the console is considered. For example advanced IC pin mods are later, also the Heat sink upgrade will leave a lot more space around the IC pins for later mods.
Detail Steps:
The following really makes it easier and improves the quality.
Not including Tax or Shipping
Console: $50
Power Supply Cap Kit: $3.95
Console Cap Kit: $9.95
4 MB Chip: $25 each Est.
Controller PAK:
$15 FRAM
$1.25 Battery Holder