Martin:
Our unit--'73 Safari--is quite different from yours, and I don't know
how much modification you want to do, but I just successfully
replaced our stop/tail/turn lights with these LED units from Harbor
Freight:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93263
It did involve modification. Basically, I eliminated the steel
"buckets" (and the part of the cast Al fixture to which they attach),
reshaped (sanding drum on electric drill) the recessed edges of the
fixture so that the new light units fit in snugly, and secured the
units with a bolt running to the inside of the trailer. The bolt
heads attach to the lamps via a scrap of solvent-glued ABS; the nuts
and washers on the inside of the trailer are concealed inside cabinet
work. Equally importantly, the edges of the lamp units are bedded in,
and caulked with, Vulkem.
Hope this helps; will try to send a couple of pics to your e-mail.
Rob
'73 Safari