Posterior. Phone appears to have not posted my last attempt at a reply.
In summary: a frame thing is coz most of the lights end up way too high off the ground.
LEDs are good but confuse some cars. 13 pin plugs are way more reliable than the non sealed 7 pin efforts.
Poly if you want to see what I did I don't think you are too far from my habitual abode. You welcome to come see my solution.