Dynamark rider

Hey guys, I think i've made my decision on the engine for the dynamark. I think i am going with an opposed twin. I will keep you updated on how it fits, but for now, the plan is as follows:
Get carbs from at least a 13hp ohv (2) for dual carbs
I will measure the bore to see if it is ovaled. If it is still round, then I will be honing it and putting rings in
Governor delete
Porting (especially on the exhaust, intake will be left alone to better mix the fuel and air)
Eyebrows?
new headgaskets
de grease everything
exhaust will not be a 2 into 1, instead i will run 1" or 1.5" pipe, one for each cylinder, side by side and do a side dump either under or behind the foot board. Y'all picture what i am saying I hope.
I forgot to mention stiffer valve springs and hopefully a cam with a little higher travel. Maybe from a 46 cube?
If anyone has experience with doing something like this, any help or suggestions is appreciated

hey guys, this thread has been dead for a few months now, but i finally made some more headway. I used a cut up gokart frame to both serve as a rear axle, and frame strengthening. Pics will be coming soon. It still sits a few inches higher than i would like, but I can live with it.
the quad rear axle is going to be used I think, but the handlebars will not be, and I am still struggling to figure out the steering for this thing.
Briggs opposed is still on tap as a possibility, unless i do a gokart style engine in the back, where the engine mount on the gokart frame is