You got to be kidding as much as it is to rebuild a stock box,no one has put in a rack and pinion in a first gen econoline. I was hoping for some pics so I didn't have to reinvent the wheel oh whell I helped put one in a 55 ford pu years ago should be about the same . . . maybe
Well, if you are doing it just to say I have it ok...if its for ease of steering, turning radius, performance...Hmmm, no.....it will actually increase the turning radius and does nothing in the performance arena.
So I have your permission? . . . I was looking at cost and keeping my hands busy. Sense my box is selfdestrucking I'll guaranty the steering will be easier. It may or may not turn sharper depending on what rack I use. Plus the option of power steering if I want (I don't). Other sites have recommended a Toyota previa or VW Vanagan because of the location of the steering column in relation to the axle, the Toyota uses a 90 degree box to change the direction of the steering column. Apparently the column is in front of the axle and the rack is behind the axle like ours not sure of the the VW setup. At the local pull a part part would be about $120 (steering column, rack and 90 degree box)
Look, I did not mean to imply you need a "permission" to accomplish this but, I was assuming you wanted something that would not only be doable 9which it is) but be effective as well.....if I may suggest, you can get the oem steering box rebuild kit (including fast steering which would reduce the number of turns by about 20%) by these guys at less than what you are looking to spend on used parts....
If the rack was mounted to the front axle it would eliminate the bump steer problem. The shaft from the 90 degree box to the rack would have to be a sliding shaft with universal at both ends. The location of the rack would be approximately where the tie rod is now. Still in thinking stage (no cash) but that's what I invision. If I get the parts from local pull a part and fab brackets I should be able to put it together for half of what they want to rebuild a stock box.