 Complete the following phrase:  Although according to Dennis Jenkinsons book Historic Racing Cars the uncompleted GP4 machine was converted and became F23 this was not correct and chassis GP4 was sold to Bobbie Baird in Ireland and eventually became a Jaguar engined 2 seater sportscar. It competed in this form and still exists as a Jaguar 2 seater sportscar. F23 was no more successful than its siblings. F24 followed in construction and was sold to Orlando Simpson before Peter Whitehead placed an order for what was to become the last Alta car built: F25. This F2 Alta was entered for World Championship Grands Prix events, first driven by himself in the 