[Christ]

That grille block looks great, the only thing I could think to have done differently is to use some high-modulus clear latex caulking to hold it in, rather than the zip ties (makes it so you can't even tell it's there, and won't damage the paint, should you ever take it off)

Although, maybe the zipties aren't such a bad idea, since caulk tends to fail after awhile.

As far as the HD lip, I've seen two kinds of them: The garden edging you're using, which as been successfully done two ways.

And the door weather moulding (comes straight, but mounts as a right angle) which is made of rubbery-vinyl stuff. (Garage door trim, basically)

The garden/sidewalk edging that you're using, the best way I've seen to mount it is to actually drill holes in the round part, all on one side, so you can insert small screws (this will be your back side, or face the engine bay.)

._
( )
.|\
.|
.|
.|


Basically, drill holes in where the slash is, all on one side, lined up with any holes that are in your bumper cover already. This way, you can use the existing holes in your bumper, and put a nut/washer on it to more securely fasten it.

The other way to do it is exactly what you're doing, except heating up the whole strip that you're using enough to create a 1/2" wide 90* flange on the flat edge of the trim. You can figure it out from there.

The other stuff, that mounts itself as a right angle on it's own, is A LOT easier to use.

Basically, mount it up from the center outward, and when you have to start turning a corner, pie-cut the "flange" that you're working with. It stays flexible even in extreme cold, and works out better for lowered cars, as it won't break if you smack it on the ground. It's a flexible vinyl. (Think: hypo-allergenic exam gloves)

Hope this helped.