Here is a pattern for a Crocheted Campervan Cushion Cover based on the 1970s Bay (though you could easily adapt the front indicator lights the make an Early Bay version!).
The finished cover measures approximately 40cm/16″ square. I’ve made the original in Wendy Serenity Super Chunky yarn (5 x 100g balls: 1 Chalk, 1Tarmac and 3 x Ivy). Each ball has approximately 80 metres of yarn so make sure you have enough metres if you use an alternative.
This is crocheted to a tension of 11 sts and 12 rows to 10cm/4 inches using a 6mm hook.
To finish the cushion you’ll also need a minimum of 40cm/16″ cushion pad. You can poke in the top corners of the pad to keep the roof shape. You’ll also need oddments of yarn in red and orange for the indicators, a small amount of stuffing and a 25cm/10″ zip.