1. Planning & Compatibility

• ☐ Define goal (cruiser, street/strip, track, daily)

• ☐ Choose LS engine (5.3, 6.0, LS1/LS3)

• ☐ Choose transmission (manual vs automatic)

• ☐ Confirm rear axle strength and gear ratio

• ☐ Measure engine bay, firewall, and hood clearance

2. Engine & Accessory Setup

• ☐ Inspect engine (compression test if used)

• ☐ Replace wear items (gaskets, rear main seal, water pump)

• ☐ Select correct accessory drive spacing (truck vs F-body vs aftermarket)

• ☐ Install low-profile intake if hood clearance is tight

• ☐ Install correct oil pan, pickup, and windage tray

3. Engine Mounting & Chassis Fitment

• ☐ Install vehicle-specific LS swap motor mounts

• ☐ Test-fit engine for firewall and steering clearance

• ☐ Verify oil pan to crossmember clearance

• ☐ Check hood clearance before final mount tightening

• ☐ Set correct engine angle (typically ~3° down)

4. Transmission & Driveline

• ☐ Install transmission and bellhousing

• ☐ Fabricate or install transmission crossmember

• ☐ Measure and order custom driveshaft

• ☐ Verify driveshaft angles

• ☐ Upgrade U-joints if needed

5. Fuel System (Critical for 1960s Cars)

• ☐ Install EFI-capable fuel tank or sump

• ☐ Install high-pressure fuel pump (in-tank preferred)

• ☐ Run EFI-rated feed and return lines

• ☐ Install fuel filter rated for EFI pressure

• ☐ Verify fuel pressure (~58 psi)

6. Cooling System

• ☐ Install aluminum radiator sized for LS

• ☐ Install electric fans with shroud

• ☐ Route steam port lines correctly

• ☐ Install correct upper/lower hoses

• ☐ Verify fan control (ECU or standalone relay)

7. Exhaust System

• ☐ Install LS swap headers for your chassis

• ☐ Verify steering box/shaft clearance

• ☐ Install O2 sensor bungs

• ☐ Connect to existing exhaust or fabricate new

• ☐ Check ground clearance

8. Electrical & Wiring

• ☐ Install standalone LS wiring harness

• ☐ Mount ECU away from heat and moisture

• ☐ Delete VATS and emissions codes in ECU

• ☐ Connect ignition switch to ECU

• ☐ Ensure proper engine and chassis grounds

9. Gauges & Controls

• ☐ Adapt factory temp and oil pressure gauges

• ☐ Install tachometer adapter if needed

• ☐ Verify speedometer solution (electronic vs mechanical)

• ☐ Connect throttle (cable or DBW pedal)

• ☐ Verify transmission shifter operation

10. Brakes & Suspension (Often Overlooked)

• ☐ Upgrade front brakes (discs recommended)

• ☐ Inspect suspension bushings and ball joints

• ☐ Upgrade springs if engine weight changes

• ☐ Verify brake booster vacuum or hydroboost

• ☐ Check steering clearance under load

11. Fluids & Pre-Startup

• ☐ Fill engine oil and prime system

• ☐ Fill transmission fluid

• ☐ Fill cooling system and bleed air

• ☐ Verify fuel system for leaks

• ☐ Double-check all fasteners and wiring

12. First Start & Tuning

• ☐ Load base tune for engine and injectors

• ☐ Verify oil pressure on startup

• ☐ Check for leaks (oil, fuel, coolant)

• ☐ Set fan temperatures

• ☐ Schedule professional dyno or street tune

13. Final Road Check

• ☐ Verify driveline vibration

• ☐ Check brake performance

• ☐ Monitor temps and oil pressure

• ☐ Re-torque mounts and exhaust

• ☐ Change oil after initial break-in