which is the good idea and which the dumb?

My wife and I are planning to make our holiday layout permanent and expand it a bit. Our garden has a walkway in it made of Trex. The trex is laid right at ground level--picture is here:



The expansion plans call for the new track to cross that path twice, parralel to the edges of the trex board. Basically, parrallel to the botom of the picture.


My wife wants the crossing to be at grade. I've been thinking of two ways to do this

1. First would be to set the track in the trex board like streetcar rails--usng my table saw, cut a groove that's exactly to guage, then epoxy the track in place. Upside is it's neat and relatively prototypica, nobody trips. Downside, I think,  is going to be accuracy--I've got to get those cuts exactly right. Would it work to do it on a table saw? Not, I'm thinking, if the edge of the trex board is uneven. I could use a router also, but I'd have the same problem--how to get two dead straight lines exactly the right width apart in my crowded home shop

My second option would be to order a few of these:

http://www.railclamp.com/sitePhotos/roadCrossing24.jpg
Image exceeds 640 pixel max. width - converted to link. Mod.

From Split-Jaw, and then to rout a channel in the trex and set the crossing piece in the channel
Upside: requires less accuracy

Downside: less prototypical, colors won't match, more expensive

Any thoughts on which would work better? I actually don't know how much leeway there is in guaging track. I'm leanign twards option two