That’s awesome about the 91 GM jack, I have a range and have had it from 50,****** miles I like it and it does the job, I also would consider a catch can.I have one from OCS and it catches a ton of oil. Also look at exactly what there doing with the lock up in the tuning as I have heard the getting rid of it all together in 2, 3, and 4 is pretty much just as bad as it engaging all the time like it does stock