The question will always have to he asked whether it's a good 8dea to use these old Simplex RDs with Delrin on its major parts, like the main pivots. Sure, it looks pretty good, condition-w8se at first glance, but who knows how much 9f the plastcizers in that Delrin had already off-gassed from it, since it left the factory 49 to 50 years ago.... why not just get an all metal Simplex RD with similar gear capacity, so you will be safe, for sure. Tue later all metal ones like the Simplex 4000 and 5000 series with the longer cages, did shift much better, because they do not have the flex that the Delrin festooned ones did. So the shifting is more precise and quicker.