I probably not going to rebuild a whole lot of a500's or a518's in my lifetime, so I find it hard to spend $100-$150 on an overdrive clutch spring compressor or the direct clutch spring compressor for a500 rebuild. I took some measurements and headed down to Home Depot, where I found a couple of electrical conduit PVC couplings had just the right dimensions. The electrical conduit is much thicker and stronger than standard PVC. The 3" coupling works for the OD spring, and the 2.5" coupling works for the direct clutch spring. If you try this, do so at your own risk. The OD spring has over 800lbs compression, and bad things can happen, especially using PVC to compress it.