1. Start by supporting the car on 4 jack stands. The car should be sitting on approximately the same angle as it does on the ground, or slightly lower in front. (If you are using a new pair of boxed frame rails, you can skip to step 5.)
2. Remove all the old front suspension components. We would recommend that at this point, you tack weld or clamp a temporary brace across the frame rails in front of the old crossmember as shown in Figure 1. This helps to maintain the rail dimension after the old crossmember is removed. Lastly, remove the old crossmember by drilling out the rivets.
3. Now it’s time to recondition your frame rails. Your frame is two layers thick in the front area. During the past 40 some years, rust forms between the layers of the frame rail flanges and swells, causing them to separate. This causes the rail flanges to actually open up, as in Figure 2A. Your rails will probably look similar to this. It is necessary to squeeze the two layers back together, using a vice-grips or hammer and block. Then, using a large C-clamp, bend both flanges back together so the rail is square again. (See Figure 2B.) It does not need to be perfect for the entire length, but it should be close in the areas where the new crossmember and spring towers mount. The better you can make the rails in this step, the easier it will be to weld in the new components. Also, grind off and weld in the rivets on the top of the frame rails.
4. The next step is to box the rails. The edges of two layers of metal probably don’t line up very well on the frame flanges. Grind them down so they are flush and straight, and the boxing plates fit tight against them. (If the boxing plates fall into the frame rails, the rails are still too wide. Repeat step 3.) Caution: Do not grind too much material off the flanges. The finished boxed rails should end up being 1-7/8″ wide in the new crossmember area. The rest of the rail is not as critical.
5. Using the center rivet hole from the old cross-member or the rear top hole from the fender bracket, mark a line around the outside of the frame rail. This is your axle centerline. (See Figure 3.)

If you purchased a complete I.F.S. Package from HEIDTS, it was supplied with Full Lower A-Arms. Begin by installing the Lower A-Arms onto the crossmember. The holes where the lower control arms attach to the Crossmember must be enlarged to 5/8”. Mount the Crossmember Spacers and the Rear Spacers which were supplied with the Lower Control Arms onto the Crossmember as shown in Figure 4 using the supplied Inner Bushing Bolts, Nuts and a temporary spacer under the Nuts. DO NOT use the A-Arms for this operation as the welding heat will melt the rubber bushings. Tighten the Bolts and Nuts tight. Weld the Rear Spacers to the Crossmember all around. Weld the Crossmember Spacers as far as possible inside the crossmember on both ends. Position the Gussets horizontally, not vertically, against the Rear Spacers and the back of the Crossmember. Weld Gussets to Spacers and Crossmember. When it cools, remove the bolt.

source

Related Tags: , , , , , , , , , , , , , , , , , , ,