The brake reservoir is in the master cylinder. Pull back your floor mat and look for a rubber plug about 3" diameter. Pull the plug and you'll see the cap.

Yes, the oil filter should be in the canister. If it's genuine Chevy it will take a Wix 51100. Most of the oil should drain back into the engine when shut off. Sounds like yours needs a good cleaning.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.