Here are some links to repair tips and reference material.

vintageTEK Museum Product Repair

150-0009-00 Neon Lamp Burn-In

1950 Tektronix Color Codes

310 Calibration Procedure January 1956

460 Series / 475 Repair Tips (video)

468 Mostek MKB36000 ROM Repairs

531 Calibration Procedure

535 Calibration Procedure December 1955

576 High Voltage Transformer Repair

The 4051 had three firmware releases during its production. This July 7, 1976 document details the corrections and the serial number breaks for the various releases.
4051 Firmware Releases

7854 Mostek MKB36000 ROM Repairs

Circuit Computer

Circuit Descriptions with Chuck Miller

CRT Database

Dallas DS1287 Dead Battery Repair

We don't know the source or reason for this document which describes the more popular transistors used at Tektronix.
Everything About Transistors

Fundamental Electronic Concepts for Oscilloscope Use and Maintenance 1956

Keytronic Capactive Keyboard Repair

Military Nomenclature / Modified Products

This undated document describes the phase-in of earthtone colors instead of the traditional Tek blue.
New Color Scheme

Primer of Waveforms and their Oscilloscope Display 1960

Repairing Plastic Knobs and Gears

TDR Slide Rule

Tektronix Modification Numbering System 1968

Tektronix Standards: Abbreviations To Terms 1967

Tektronix Standards: Glossary of Technical Terms - Electronics 1967

Tektronix Standards: Terms to Abbreviations 1967

Tektronix Vacuum Tubes

Troubleshooting Your Oscilloscope

Using the Oscilloscope as an Instrumentation Maintenance Aid 1958

vintageTEK Repair Videos

  • 7L12 Spectrum Analyzer Plug-in
  • Casting a Replacement Knob
  • 468 +5V Storage Supply