Dear Welder Series… Mustang II frame width min/max

Dear Welder Series…
Hello, I’m inquiring about the Mustang II crossmember kits. A couple of questions specifically related to the 56″ track width. What is the minimum and maximum frame width measured on the inside? When using the 56″ crossmember do I purchase a narrower rack and pinion?
Thanks in advance for your response. I first saw your items used on the SPEED channel. Great stuff. Can’t wait to do business.


Dear Ken…
Ken, the min/max frame width depends on the height of the frame relative to the spindle height. The 56″ crossmember is 30″ wide. The inner edge is 25″ at the top and 19″ at the bottom. The top is 3″ above spindle height.

If your frame is 30″ wide, the coil spring might touch the upper outside corner of the frame, again depending on the ride height. Builders put a small relief in the frame for clearance. (’42-48 Fords are an example.)

All of our kits use stock MII or ’79 and newer T-bird power racks. Use our spacer kit to put the T-bird rack axis in the correct spot.

Thanks for the questions.

Paul Horton


Dear Welder Series…
Paul, I finished making up my new 2X3 front frame rails. They are 29″ from outside to outside. They are also parallel. Here is my question: I located what I would like as my spindle height and came up with approximately 1/2″ to 3/4″ from the top of the frame rails. Is this going to work or do I have to run drop spindles. I really don’t want to run drop spindles. I need to use the 56″ crossmember as planned. Let me know. I plan to order next week. Thanks again for all your help. Also I plan to air bag the front end to drop it on the ground at shows.

Dear Ken…
Ken, with stock spindles, the top of the rack bellows (the rubber boots at each end of the rack) will be about 3/8″ lower than the spindle height. With stock spindles, you will have to c-notch about 2″ up from the bottom of the frame. With dropped spindles, you might not have to c-notch at all.

I hope this helps with your spindle decision.



  1. gerald bates says:

    Paul, can your weld-it series x-members be turned around backwards to create a rear steer instead of a front steer?

    I’m building a frame for a 34 dodge coupe out of 2×3 rec tubing ,if I go with the 58″ x-member am i right in thinking i will increase the inside frame width by 2″? thanks jerry

  2. Paul says:

    Sorry, it’s not as easy as that. Mustang II spindles aren’t designed to
    be rear-steered. Heidt’s, TCI, and Kugel all use a spindle that they
    designed to be rear-steer. Usually, a Chrysler rack (Omni or K-car) is
    used and these racks have different mounts from the MII.

  3. Phil Metsker says:

    Welder series, I was wondering if there is a cross member to fit my 37 International truck that has a 28 inch frame width outside measurement? Thanks for your help!

    • DW says:

      Hi, Phil. I like International trucks but don’t know the track width or frame specs for the different models. We make kits for track widths of 56-1/2”, 58-1/2”, 60-1/2”, and 62-1/2”. We define track width as the dimension from wheel mounting surface to surface on the rotors. For a 56-1/2” track width, the easiest frame widths to work with are between 26 – 30” outside. As the track width increases by each 2” increment, the “easy” frame widths also increase by 2”. For frame widths larger or smaller than the “easy” widths, the frame can be stepped in or out to accommodate the crossmember and towers. There is some info about this at

      Thanks for considering Welder Series parts for this project.
      Paul Horton

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