Downgrading

There are still at least 2 lingering questions I have on this stuff.

Are your yards usually strict with the dimensional limits? My yards here say no more than 3 foot or less than 1/8"

If there is a piece or two which are 3 foot 6 inches, will they downgrade the load for that?

If there are heavy cast waterpumps etc, having a thin backing plate on them, will this kill the better grade ?

I am trying to get a load of this stuff together, having mostly cast iron car parts, heads, pumps, steering rods, crankshafts etc, but something like a washing machine gearbox (also mostly cast, but several thinner than 1/8" mounting plates welded to it ), and I'm just hoping I'm not wasting my time hoping to schieve the better price