Vacuum Pipe Diagram
Over the years, Lotus added a lot of extra vacuum pipework as part of an attempt to control emissions.
It's common for perished hoses or failing "vacuum switches" to lead to problems.
The "vacuum switches" are still available as Jeep parts, but a check of the condition and location of all hoses is a good starting point for curing many idling and fuelling problems.
Bryan Barker produced this helpful diagram, of the final arrangement, which shows all the hoses in their original factory colours. Colour is not important, but the end points are. (Earlier cars don't have the carb. "F" pipes, and LC engines don't have the vac. advance on the distributor.)