Glow plug relay overide?

[peachykeen]

I have a very, very high mileage 79 300TD wagon that has become really hard to start 30s even mid-low 40s F...glow plugs are good, fuel has powerservice in it regularly and valves have been adjusted in last couple yrs...plus a recent full diesel purge...

Has anyone overrided their glow plug relay to manually control the time that the plugs are actually glowing? If I am correct, if I could allow my plugs to glow longer, won't my old wagon start a bit easier this winter? There is a place online (**************) that sells a little kit to do this and wondering.....

Thanks for any insight.