Dave covered some good points. I changed the standard steering in my GMC Safari van to rack and pinion. Here's a few more pointers. The rack should have enough travel to put the steering knuckles against their stops. The rack and tierods should be as close to a straight line as possible with the attaching points on the knuckles. Don't worry if they are a few degrees off. Just get them as close as possible. Use a rack from a vehicle that's close to the weight of your finished vehicle. Metric is no problem. Almost all rack and pinion units in modern vehicles are metric. When I changed mine I used all over the counter stock pieces with the exception of the pressure hose which had to be modified to fit a GM power steering pump and a Ford rack and pinion. If you are not using power then that's not a problem. The column link will probably need to be fabricated from scratch. I had to add an extra u-joint which meant there had to be a support to hold the column ridgid. I used a 3/4 heim joint. In my case it wasn't nearly as challenging as most would think. It's been in the van for several years with no problems. Good luck.