Just one way of many methods some are better(homebrewed or bought) of converting to tbi and trying to keep some authentic semblance?,bit pricey method of skinning a cat though.
http://pattonmachine.com/TBI-Main.htm
and mentions for early hitachi 240z http://pattonmachine.com/TBI-Pricing.htm
http://pattonmachine.com/TBI-Main.htm
and mentions for early hitachi 240z http://pattonmachine.com/TBI-Pricing.htm