AD Rear Cab Mounts for 47-53 Chevy Truck Instructions

Important Notes

Hardware to bolt the cab mounts to the chassis is NOT included — suggestions on hardware to use are included in the printed instructions.

Addendum for 1947 Chevy 3100: the 1947 Chevy 3100 does not have existing holes to locate these aftermarket mounts. Skip to Step 3 to get the proper measurement for the rear cab mount location — it should sit slightly behind the center running board mount. There are no holes in the cab floor; install the rear cab mounts, place the cab on the chassis, square it up, then drill holes using the mounts for location. Whether bolting or welding, carefully measure your rear cab mount location to assure proper fit.

Attention: to properly install the Apicella Designs 3100 rear cab mount kit, the cab must be removed from the chassis. Do not attempt to remove the cab without sufficient knowledge, adequate tools, and proper safety measures — doing so could lead to severe property damage, injury, or death. Apicella Designs LLC assumes zero liability for such occurrences.

Chevy 3100 Rear Cab Mount Install Steps

Locate and drill. Once the cab is removed from the chassis, locate the two holes where the rear shackles were mounted and drill them to 7/16″ in diameter.
Mount to the chassis. Use 7/16-14 x 1 ¼″ bolts to mount to the existing shackle holes. If the cab mount doesn’t sit square to the chassis, use the included 7/16″ double-thick washers between the cab mount and the chassis.
Measure. Center of the front cab mounting hole to center of the rear cab mounting hole should measure 36 ¾″ — measure both driver and passenger side. Front cab mount center-to-center holes measure 47″; rear cab mount center-to-center holes measure 49 3/8″. The mounting holes are slotted, so these are approximate — get as close as possible and tighten all rear cab mount hardware.
Drill pilot holes. Once measurements are confirmed and hardware is tight, drill through the 1/8″ pilot holes already punched in the top of the mounts, carefully drilling through the chassis.
Open up the holes. Open the pilot holes to 3/8″ — a step bit works well and keeps it clean. Deburr the holes after drilling and install the 3/8-16 x 1 ¼″ bolts, washers, and nuts (not included).
Install bushings and spacers. Before placing the cab on the chassis, place bushings and spacers: front mounts each get a polyurethane bushing sitting directly on top of the front cab mount, with a 3/8″ double-thick fender washer inside the cab and a 3/8 x 2″ large fender washer directly beneath. Front mounts use a 3/8-16 x 3″ Grade 8 bolt and Nyloc nut. Rear cab mounts use the same setup plus a 1 5/8 x 2″ Delrin spacer directly below the polyurethane bushing (order: 3/8″ double-thick fender washer, cab floor, 11/16 x 2″ polyurethane bushing, 1 5/8 x 2″ Delrin spacer, rear cab mount, 3/8 x 2″ fender washer), using a 3/8-16 x 3 ½″ Grade 8 bolt and Nyloc nut. Double-check the tightness of all bolts during assembly.

Stop — Double-Check Before Drilling

Double-check all measurements prior to drilling. Verifying every measurement assures the fit and finish of your Apicella Designs product. The customer assumes all liability for any modification to this product and/or the vehicle being modified.

Note the 1947 3100 addendum above — the earliest trucks need the extra step. Cab mounts, firewalls and interior panels for the whole generation are in our 47-54 truck parts collection.

For any questions or concerns with your install, don’t hesitate to email us at info@lsfab.com