That G&P head is interesting. Cabelas doesn't make thier own flashlights of course, but that one looks very different.
I don't have any D36 modules (was hoping someone else would confirm the fit first

), but this cabelas head is probably wider and deeper, so with some padding it might work. There might be a problem if the D36 module is too shallow, because it might hit the aluminum inside the head before the base makes contact with the body, and making a conductive spacer behind it would be harder.
Of course this is all just speculation until someone tries it...
I have 5 D36 modules.
1 stock 9v
1 stock 12v
2 E0-9L's
1 Extremely crappy Cree P4 LED module.
All these modules are much shorter than the stock G&P modules by 5/8's of an inch maybe more.
Both the 9v and the E0-9Lwill fit in the head.
The 9v achieves good conductivity as is and will light up as is. That is without the bezel on as soon as the bezel is screwed on and you attempt to use the light normal the gap inside the head (because of the shorter module) will allow the module to slide forward and break electrical contact shutting of the light.
The E0-9L will not achieve good electrical contact as is. I do however have laying around a couple of spring that come on the bottom of most D26 modules you buy from chinese vendors. Like the spring pictured here.
When I place one of these into the cavity of the head as it would in a D26 module and then place the D36 module on top of this the light will light up. The same sliding problem as with the 9v still exists however.
In both instances a little downward pressure is necessary to achieve good contact.
Now if I stack two of these springs on top of each other the combined length of the two springs plus the module is enough to ensure a good rattle free fit. This however creates a another problem now the inner spring is too short to make contact and the batteries slide too far forward to make contact with the tailcap spring.
At this point I would have two options (that I can think of):
1. Engineer some sort of longer inner spring to make contact with the top of the batteries so they don't slide forward and allow the light to work.
2. Engineer some sort of space to fill the gap between the tailcap spring and the batteries (aluminum foil and tape anyone).
There is also a possibility that one could just go with the one spring in the head (instead of two) and fill the head with enough o-rings to fill the gap.
Bottom line I think this can work.
At any rate thats all for now (I just got in - long day) I hope that helps.