After doing a cam job on my 327 SBC. I drained the break in oil to add new oil with a little ZZDP and a new filter. I had wanted to add a magnetic plug for a little piece of mind. I looked everywhere in the shop , cause I thought I had one. Couldn't find it. It was 3 in the morning but I wanted to drive the Roadster the next day to work. So I put the old plug back in and topped it off with the aforementioned oil. I was telling a guy at work about it and he said when he was working for Ford they ran a plastic plug on one of their diesels and it always leaked. The way they changed it was put a shop vac on the oil fill and secure it . Turn it on and change the plug and it would slurp air but never lose a bit of oil. Well I bought my plug and went home and put my shop vac on the oil fill tube on my SBC at the front of the intake. I had a reducer that fit in it perfect. turned it on and had a friend watch the hose. But it could be secured with duct tape ,etc. if you are doing it alone. Got my new plug with thread sealer and pulled the plug. Not a drop of oil came out you could look in the hole and see the oil as it slurped gulps of air through the drain hole. put the new plug in and tightened it up. Shut down the vac and checked the shop vac hose. There wasn't a drop of oil in it. Hope somebody else can use this little trick if need be. Happy Motoring!