Just bought first Chevelle and need some part info. What piece goes between the grill and bumper on a 65?

There is a splash pan in that area. It bolts to the under side front edge of the front fenders and ties the fenders, inner fenders and the hood latch support together. This piece also completes the inner fenders to help keep debris out of the engine compartment. If I recall correctly, the turnsignal light wiring has a rubber plug that fits through holes in either end of the piece too.

In the event you are wondering, the piece is unique to '65's, in other words, the similar piece from a '64 or '66 will not work on a '65.