Hi - am rebuilding the mc and bought a rebuild kit for it. All the parts are the same on disassembly except for the spring. The spring I took out is about 2 turns longer than the replacement one. It still is quite firm.I am thinking I should reuse the old spring with new seals, etc. it's off a 37 gmc half ton. It's a delco. I'm pretty sure I bought the right rebuild kit off jim carter as the rest of the parts match exactly. Any advice? Also was going to paint it cast iron grey. Was it originally black?