Spectra Premium Squarebody 1987 + Sending unit for LS and EFI

Upgrade your Squarebody Chevy or GMC truck fuel system for EFI and LS power with the Spectra FG05M (Driver Side) and FG05N (Passenger Side) EFI sending units. These OE-style replacement units allow you to drop a high-pressure fuel pump directly into your factory-style tank – the cleanest way to fuel your LS swap or EFI conversion project.

We recommend pairing these sending units with a 1987+ fuel tank for best fit and compatibility with modern EFI systems.

Why Choose FG05M & FG05N for Your EFI Build?

• ✅ Direct-fit for Squarebody tanks – Designed to replace factory sending units
• ✅ EFI-ready design – Supports in-tank fuel pumps for clean and quiet operation
• ✅ Perfect for LS swaps – Get the pressure and volume your new engine needs
• ✅ Choose the correct side – FG05M = Driver side / FG05N = Passenger side
• ✅ Works with multiple pumps – See options below based on horsepower

Recommended In-Tank Fuel Pumps:

• 🔧 Spectra 190LPH Pump – For stock LS swaps up to 450HP – Click Here
• 🔧 Walbro 255LPH Pump – Supports builds up to 600HP – Click Here
• 🔧 Aeromotive 340LPH Pump – For high-performance setups up to 850HP – Click Here

Don’t Forget Your Adapter Fittings:

These sending units feature factory-style hard line outlets (3/8" & 5/16") and require adapter fittings to convert to AN-style fuel systems:

• 🧰 Hard Line to AN Adapter Fittings – Click Here

Fitment & Compatibility:

• ✔️ Designed for Squarebody Chevy/GMC pickups (1973–1987)
• ✔️ Compatible with EFI fuel pumps
• ✔️ Recommended upgrade to 1987+ fuel tank for best performance
• ✔️ Choose FG05M (driver side) or FG05N (passenger side) based on your tank configuration

Tech Tip:

Mounting an in-tank EFI pump helps eliminate external noise, prevents vapor lock, and makes your build look cleaner. Combine this with our AN PTFE hose kits or LS Swap kits for a complete EFI-ready fuel system.