I had a '68 MGB with 2 SU carbs and a cable linkage. I was about 3 miles from home in heavy traffic and the cable end gave it up. My roadside fix was to put a book of matches under the idle speed screw and bring the idle up to about 1800 rpms. Drove home like a piece of heavy equipment. Only got funny looks at stoplights. At least it got me home.
my hj45 was the one i busted the throttle cable on (in the middle of nowhere, and no one in victoria that i could find stocked one), my solution was similar to the matchbook, but i just used duct tape on the throttle where the cable hooks up, to get the revs to sit on about 2300 rpm. really reved the t!ts off the old diesel on the 4 hour journey, but at least i got about a 80 Km/h top speed. it was a long trip, and people thought i was wierd at the lights too