1968-1969 Front Plenum Panel Extension - LH - 3918593 - OEM Number(s) (3918593)
Secure proper fender alignment on your 1968–1969 Corvette with this Front Plenum Panel Extension – Left Hand. This OE-style press molded fiberglass extension fits between the cowl and fender, increasing structural stability and providing critical surface area for bonding the front fender to the plenum. Whether you're restoring a survivor or rebuilding after accident repair, this panel ensures factory-correct fitment and structure on the driver side.
Features
• Fits 1968–1969 C3 driver side front plenum area
• Provides bonding surface between fender and cowl
• Made using press molded fiberglass for factory-correct finish
• Reproduced to original GM shape and contour
• Made in the USA for quality and authenticity
Dimensions and Weight
• Application: Left Hand (LH), Front Plenum Extension
• Material: Press Molded Fiberglass
• GM Part Number: 3918593
Because Fit and Finish Matter
This plenum panel extension plays a vital structural role in supporting and securing your C3’s front fender. Using the correct press molded part ensures both restoration accuracy and bonding integrity—without compromise.
Hand-Laid vs. Press Molded
Original GM panels were press molded—a production process using high pressure and matched dies to produce thin, consistent fiberglass with smooth inner and outer surfaces. These parts were fast to manufacture but prone to stress cracking and distortion with age.
In contrast, hand-laid fiberglass is manually built up with resin-saturated mat, resulting in thicker, more durable panels that are stronger and easier to modify or reinforce. While slightly heavier and with a rougher backside, hand-laid panels are ideal for restorers seeking long-term structural integrity and excellent fitment—especially when factory press-molded panels are no longer available.
Learn more from the following Mid America Motorworks Knowledge Library article:
Corvette Body Components from Fiberglass to Resin Transfer Molding
Also known under these part numbers: (For reference only)