Classic/Antique Car Repair: 1948 Chevy 3/4 Truck, clutch linkage, clutch fluid

Question
Recently, after leaving it for about six months in the garage, I decided to take my truck for a short ride but I could not engage the gear. It just gave off a grating metal against metal sound. This never happened before and after multiple unsuccessful attempts, I shut off the engine and put it in reverse and then started the again and immediately the truck took-off backwards. I shut the engine off just in time before I ran into the garden wall. I consulted a friends who knows more than me and he thought it might be that the oil reservoir might be low and suggested that I top it up with brake fluid and pump the clutch and try again to see if it will engage the gear with the engine running. I have to say that there is some oil discharge from the engine block but it may also be coming from the clutch fluid (?) reservoir. Before I start experimenting further, do you have any advice/remedy?
Many thanks for your help in advance.
Sincerely yours,

Answer
If the truck is stock the clutch linkage is mechanical and not hydraulic. It sounds like the clutch disc is stuck to the flywheel. In some cases you can snap it loose by putting the transmission is high gear, and hold the brake on really good, and holding the clutch to the floor. Then start the engine. In reverse the gearing is such that there was not very much pressure applied to the clutch to break it loose but the gear ration in high gear will put more pressure on the disc. Be ready to shut the engine down if the clutch does not release and the truck begins to take off. If this does not work the transmission will need to come out and the clutch removed and replaced.