Williams Classic Chassis Works

Mini Tubs

 

Remove all carpet, padding, rear seat, etc. in area of rear fender wells.

 

Disconnect battery ground cable.

 

Using a sawsall or similar tool, cut out the sheet metal between the package tray and the floorboard on both sides next to inner fenders. Use the bottom edge of the package tray as a guide while cutting out completely flush to side panel above fender panel. Flush to side panel above fender panel.

 

Cut material between hinge wells and inner fenders. Finish flush with bottom of hinge wells.

 

Layout removal of stock inner fenders as follows:

 

A. Measure at top of inner fender well from side panel inboard 1 1⁄4” to 1 1⁄2” and mark. This flange that you will cut to size is where the new tub fits up to from underneath and overlaps.

 

B. Layout a cut line forward that intersects the floorboard at 90 degrees and about 4 1⁄2” inboard from vertical body inside panel. We use 1" masking tape as a guide.

 

C. Layout cut line towards trunk area starting at center/top reference point of 1 1⁄4” to 1 1⁄2” and taper gradually inboard to where it meets trunk floor surface about 23" from lower trunk seal flange and 4" inboard to start with. I highly recommend pulling trunk lid off, it makes the job that much easier. You’ll final fit the tub later, you just want to rough out the shape for now. You’ll have to be very careful not to cut too much away, especially in the trunk area at first.

 

D. We use a combination of a sawsall, 4" Makita cutting blade, air chisel, and plasma cutter to do the cutting. Take your time!

 

E. To establish the front floorboard cut, use a flexible straight edge spanning the front leading edges of original inner fender at floor and draw cut lines inboard towards and flush with frame rail.

 

F. Read all instructions before you decide to guess.

 

 

 

 

Welding Tubs:

 

After you’re happy with the fit, you’ll need:

 

A number of clamps and small pieces of scrap metal

An old hammer handle to apply pressure from inside the tub during the welding process to keep fit tight

A patient friend to man the hammer handle or similar device while you’re in the trunk welding

A TIG or MIG welder is recommended

 

Use straight­edges, squares, angle finders, and any straight or parallel surfaces to reference tub surfaces off of.

 

We use the clamps and scrap metal pieces to position the tub side panel surface above the frame rail and help hold up against the floorboard.

 

Look at the sketches and photos once more before starting your tacking. Begin at the top and work your way towards the front of the car in 3/4" increments.

 

Do the same towards the rear of the car.

 

Be sure your friend underneath is holding the tub as high as possible to ensure a tight fit and better weld.

 

Weld along the floor line the same way, starting in the middle.

 

NOTE: If using a wood or other flammable devise for step 6, be sure to keep it as close as possible but be very cautious of starting fires.

 

You can now tie the hinge wells for the trunk into the tub at the inside edge with a strip of 1/8" steel.

 

Prep all welded joints and use a good quality chalking sealer to finish off. A chalking gun works great if you have access to one.

 

NOTE: It’s not necessary to weld up 100% and could cause warping.