Taillamps

[chevyhed53]

OK, friends: Try to follow this one, and I appreciate any suggestions.
Got new tail lamp units and correct brackets for my '56 stepside. Tail light housings from Eckler's, the brackets from Jim Carter.
Tested to see which wire (black or white) from the unit goes to which wire on my Haywire setup. So far, so good.
Got everything hooked up--brackets nicely bolted to the truck, taillamps wired up correctly--and, of course, all I get is a very dim flash on the turn signals and flashers and NOTHING on my tail lights.
OK. I hook up the test light and turns out the whole housing is hot--everywhere I touch on the housing when the headlight switch is on is powered. So, I run a ground wire from each unit--from one stud on each unit to a nice spot--rubbed it clean--on the bumper brackets. That cured the hot-all-the-time issue, but not the basic no-taillights issue.
Then, almost by accident, I laid my test light--which was grounded to the tailpipe--from the socket (I obviously had the lens off) to the small bracket where the lens screws in, and voila! The lights go on.
So, I obviously have a ground issue, but how do I solve it? It appears the housing still isn't properly grounded, but it also seems like the socket isn't properly grounded to the housing!
Sorry this is as long as War and Peace, but it's been a weird day.
Any suggestions are appreciated!
sr