Southern California's Mustangs Etc. is a treasure trove of rust-free used and new-old-stock parts for classic and late-model Mustangs. So it came as no real surprise when their body shop wanted to use N.O.S. Ford sheetmetal for a full-scale restoration on a '66 convertible believed to have belonged to Frank Sinatra. We're going to show you in a very general style how to replace a quarter and tail panel on a '65-'66 Mustang, so this is more about technique than step-by-step. When you're performing sheetmetal replacement, good preparation is 95 percent of the end result, so that's mainly what we're going to show here.
So it came as no real surprise when their body shop wanted to use N.O.S. Ford sheetmetal for a full-scale restoration on a '66 convertible believed to have belonged to Frank Sinatra.
1a In business since the...
1a In business since the mid-1970s, Arnold Marks has amassed a warehouse full of N.O.S. Ford parts...
1b ...This is genuine Ford...
1b ...This is genuine Ford sheetmetal--right-rear quarter-panel, rear GT valance, and tail panel.
2 Before replacing quarter...
2 Before replacing quarter and tail panels, always adjust and fit-check the doors and decklid beforehand. Here, Gilbert Bravo and his father Rocky fit check the decklid and get the gaps perfect before donning the grinder and spot weld cutter. Doors will also be fit checked.
3 Eastwood’s spot-weld cutter...
3 Eastwood’s spot-weld cutter bores through factory spot welds, and if you’re careful, you can get a lot of mileage out of cutter tips. Sometimes, it’s not easy to see the factory spot-welds, which calls for guide coat shading of these areas to find them.
4 When a spot-weld cutter...
4 When a spot-weld cutter won’t get the job done, resort to a good grinding wheel and cut just short of the seams. Then gently sever the seams with a chisel or spot-weld cutter. Be careful not to distort the sheetmetal at seams.
5 The tail panel gets the...
5 The tail panel gets the same treatment with an Eastwood spot-weld cutter. When you’re cutting spot welds, bore through the first layer of steel, then stop there. Take it slow to gently work your spot-weld cutter at low speed in an oscillating motion.
6 Gently separate the tail...
6 Gently separate the tail panel from the corner gusset. Once sheetmetal is distorted, it is hard to get it straight again because you’ve stretched the metal.
7 Cutting quarter-panels...
7 Cutting quarter-panels away from the seams enables you to freely access seams for separation without risk of distortion.
8 Once the spot welds have...
8 Once the spot welds have been bored, the quarter-panel remains can be peeled away from the B-pillar. Extra care must be taken to prevent distortion.
9 When spot weld cutting...
9 When spot weld cutting isn’t effective, grind the remaining seams down to the base metal.
10 Quarter-panel removal...
10 Quarter-panel removal sometimes yields a rotted wheelhouse. Here, Rocky bores out the factory spot welds where accessible. The rest is removed with a cutting disc and grinder.
11 The N.O.S. wheelhouse...
11 The N.O.S. wheelhouse is fitted and prepped for installation.
12 Rocky and Gilbert recommend...
12 Rocky and Gilbert recommend securing panels with sheetmetal screws before welding to insure proper fit.
13 Contact surfaces are sanded...
13 Contact surfaces are sanded bare for good welding adhesion. If you’re concerned about corrosion, opt for weld-through primer. All of these small holes punched with an Eastwood hole puncher are for rosette welding, which offers a more secure bond than factory spot-welding, although you can use a spot welder for integrity and authenticity.
14 The wheelhouse is rosette...
14 The wheelhouse is rosette welded in place prior to quarter-panel installation.
15 This is what rosette welds...
15 This is what rosette welds look like, which are ground smooth so they vanish. Gilbert says you can use a 3⁄8-inch tip center punch to get a simulated spot weld as long as you support the punch with a body dolly from behind.
16 Rocky hangs our red-primed...
16 Rocky hangs our red-primed N.O.S. Ford quarter-panel. Fitment is very challenging because there are so many contact points to cover. Begin fitment from the top down. Again, use self-tapping sheetmetal screws to secure the panel before rosette welding begins. Check door and decklid fitment first.
17 Once the quarter-panel...
17 Once the quarter-panel fit is established on top, move to the bottom and get all the seams confirmed before running screws down. This seam at the rocker panel is rosette welded inside below the quarter window. Wheelwell seams are rosette welded approximately ½-inch apart, yet spaced out timing-wise to prevent distortion.
18 The quarter to tail panel...
18 The quarter to tail panel gusset has been stripped and straightened, then clamped in place for fit check.
19 Always use factory alignment...
19 Always use factory alignment holes when checking fit. Taillight mounting holes are also panel alignment holes. Sheetmetal screws are used to secure the panels prior to welding.
20 Rocky performs a decklid...
20 Rocky performs a decklid fit-check prior to welding. Because this decklid was fitted to original sheetmetal, it's the perfect reference point. He also measures diagonally across the trunk opening and compares his findings to Ford's factory specifications, which are located in the Shop Manual.
21 The tail panel fuel neck...
21 The tail panel fuel neck gusset is dollied and readied for installation. As with other sheetmetal, it will be secured with sheetmetal screws initially, checked for fit, then welded.
22 Quarter-panel end caps...
22 Quarter-panel end caps are also good fit reference pieces, although imperfect by design. Before welding, install the end caps and do a fit check. MM