This long-awaited reissue is a perfect excuse to comb the library and locate any books or magazines featuring photos and historic details of the car as it ran at Indianapolis in 1968. Here's what I've uncovered so far.

Turbine Grand Prix by Gerard Crombac.
Automobilia, 1989.
Pages 36-59 contain more than enough drawings and photos to
help detail this car. It's also a great reference for other cars:
the '67 turbine, the Rover and Howmet cars, and the later
Lotus turbine GP car.

The Checkered Flag by Ivan Rendall.
Chartwell Books, 1993.
Page 257 shows the front row at Indy in 1968 with two of the
turbines, nos. 60 and 70 driven by Joe Leonard and Graham Hill.
This book contains many excellent photos of F1, Indy, and Sports
Cars from the last 100 years.

Design and Development of the Indy Car by Roger Huntington.
HP Books, 1981.
Pages 142-145 have very good black and white photos and text covering
the Lotus turbine cars. This book is a very good reference work for early
indy cars. It's also hard to find, so buy it if you see it.

Lotus: All the Cars by Anthony Pritchard.
Aston Publications, 1990.
Page 116 has a nice PR shot of Graham Hill in number 70.

Road and Track, August 1968
Page 65 has two black and white engine and cockpit photos.