Bummer. To replace those bushings the lower control arms have to come apart from the spring pan and the trunnion. Essentially the entire front suspension must come apart to access those bushings. As a minimum, the arms must be separated from the spring pan and the trunnion. You MAY be able to accomplish this by placing a jack under the spring and then undoing the 6 bolts holding the pan to the arms...but that will be difficult to say the least. Over time the rubber bushings take a set that is never exactly centered over the pin. So trying to replace only half of a bushing will never work, as you are trying to push a symmetrical bushing in a bore and over a pin which are not.
The original TR2 used a rubber only bushing, but it was changed to a steel/teflon affair midway through the TR3 production. If your bushings are original on a TR2, the inner pin will be heavily pitted. The newer design takes this into account by also providing a steel sleeve to cover the pin, and then teflon bearing surfaces over that. It's a better set-up all around, and I really recommend you switch over while you are there.