The 1"x4" LED strip sold by Lambert Enterprises (
www.lambertenterprises.com) works extremely well in the Lucas rectangular tail lights. It is necessary to use a Dremel to take out the extra plastic etc in the lamp assembly to make them fit, but it is easy and very worth it. In both my case and Blackjack's, the flasher worked as normal. It is true that the lLED's will draw a lot less so some of the older heavy duty flashers will not operate. You only have to go to a new style flasher to get them to work. No real issue. Check Lambert - great guy with lots of good advice and help. They really work!!!!