Pardon me, but I think you are confusing the guy... If the engine indeed is a TD (?), why fuzz with a glowplug timer for a Tdi? Using this, it will only make the plugs lukewarm at best, not glowing and ready to start cranking.
The TD, and the n/a, has a different system as you have found out by now. My 110 has no relay, just a thick cable from the ignition switch to the rearmost glowplug as standard.
There are however more effective glowplugs around that need only 5-10 seconds to glow. Here (Sweden) I bought a set at an accessories shop and recommended for Peugeot J9 van. Made a big difference when coldstarting my n/a,
Sorry if I kick in open doors...