if theres a will theres a way. there are plenty of ways. what i would do is stick a strip of metal inside the triangular tubing all the way to the dropouts back wheel axle hole. drill, bolt, w.e. you got a reinforced deck.
right thurr
so basically your getting tubing to fit in the cone shaped dropouts
smaller sized square tubing will fit
and you just push it in as far as you can
and drill through the axle holes
cut off the excess
and your shits good
but remember to make sure the tubing goes right to the end
because it might move quite a bit when you take off your axles
drilling holes through annd putting bolts through to hold it is optional
you can also reinforce the forks with circular tubing
put it in and hammer it down
trolley bars fit
thats all i know