So I've always wanted a mega Gargant for my ork army, but friggin hate the model. So I decided to convert the crap out of one to make it more detailed, and more importantly more "Orky". Here's what I have so far. I'll do my best to log where all the pieces are coming from so you kids can follow along at home!

All the white stuff is cut plastic card and rod. The rivets are made my "mincing" a very small plastic rod into tiny discs and then gluing them into place. Warhammer shields made a nice spacer for the missile launcher platform, as well as a "neck" to put some distance between the head and body.
I cut a warboss in half and glued him onto a turret gun from another Mega Gargant model. The hatch was made with plastic rod discs. The turret gun was replaced with a 40k ork boy shoota.
All of the gun deck turrets will have their barrels replaced with a random assortment of weapons to make it all look more chaotic. Blank areas will be filled in with details such as extra plastic rod kannon and random metal plates.
I bought a set of Killa Kans and their bits will be used to deck out the Gargant with details. So far I've used a missile for the first gun deck turret, as well as shoulder plates that help widen the Gargants profile (just glued them onto the "official" shoulders, as well as arm "ball-n-socket joints" under each shoulder plate that will be used for this monsters new arms.
I never liked how the mekboy weapons are mounted on those wimpy towers, so I moved the Krooze missiles to one shoulder, while the Lobba and Lifta Droppa arm will be mounted on the other.
Anyways, that's it for now, I'll keep you posted as I make progress.