OK

Yess , the led is very dim.. it is easiest seen in the dark through the rear window .
So, from your last post, I believe yu have a bad contactor set on the K38.
When the led is on , the relay pulls the contacts to the Armed circuit, but the are the same contact that interupts the starter power from the ign sw. So, you can not start the car ..
I have the schematic up [ sorry I can't send it b/c my scanner has been sent to Fl.. I am in a moving process] maybe someone can post it and I can walk you throught it..

Anyway.. here is the wiring.. just draw it from this and you will see whats supposed to happen.

Red+ goes to ign sw...this is BAT power for all ign sw.
Start position of ign sw is term 50.. this is large Violet wire
This V wire goes to K38, term 1 [87 0n relay]
When alarm is not activated, the power from #1 comes out of K38 relay at term 3.. this is V/Gn wire. [ note on schematic .. these two wires are jumpered on Canadian models , ie/no alarm disable] ..these are the contacts I suspect in the relay and that is why I mentioned jumping here for K38 contact test.. 1 & 3 jumper will eliminate the K38 circuit/relay starter interupt.
This #3 V/gn wire coming out of K38 now continues on to term 50 at NSS
[ I am sure you see where we are going now] That is why we looked at NSS/50 for power.
Coming out of NSS at 50R is V/Wt which goes to the terminal board at the firewall, center term...[ which you already know]...and from there down to the starter sol

Hell of a way to get a schematic to ya .. but if you just draw that out from
beginning to end , you will have it. Just draw 4 boxes and connect them as I printed
ign box.....K38 box....Nss box.....starterbox
Thats the sequence , now just run a connecting wire from ign right through to starter , using the terminals I mention on each, in and out ..
It is just a simple Series circuit that has to go through a few saftey/alarm contacts to get from the ign sw to the starter solinoid. You just have the fun of finding out which one doesn't like you.