I was wondering, are there any models of the M1114 up-armored Humvee, or any aftermarket kits to upgrade other Hummer kits like the Tamiya ones to the M1114 configuration? If not, what would be involved in scratch-building this conversion?

Mig Productions makes the M1114 Conversion, and it includes doors, new top, grill, and a slew of other bits.
R&J Enterprises still has them in stock I believe and cheaper than retail.
It's a good conversion set that's well done.

Here are some pics of MIG Productions conversion set :




HTH
Frenchy

And this is compatible with the Tamiya kit? Also, how would I go about getting a gun shield for one of these, and is there any after-market for mounting an M249 in place of the .50 cal or Mk-19?

Blast Models has released several sets for the Tamiya Humvee, including a complete late type weapon ring with gun shield (set #BL35050K) :
http://www.blast-models.com/page%20catalogue/bl35050k.html

HTH

Frenchy

Geez, a Ma Deuce AND a SAW? That's one of the most heavily-armed hummers I've ever seen, short of missiles! Didn't know they could mount two guns up top at once, other than the guy having his M16 or M4 lying on the roof next to him.

Yeah, I've seen images of Mk-19-armed Humvees with SAWs. They are able to do this by mounting the SAW to the rear to provide rear security. Also there is a side-effect of being able to choose how to confront a threat. Sometimes a exploding grenade from a MK-19 is not the best way to handle the situation.

Jeff

Hey Chris , the MIG kit fits pretty well with the Tamiya kit . I got started on mine a few days ago , just have the Dremel tool on stand by for clean up . About the only gripe that I have is that there is no gun shield or basket with the kit , so I'm scratching one up . later on , toad