There is a outfit around here that does pretty much all of the curb cutting for driveways exactly like you described, horizontal. And from the cost of the machine you can see why... https://www.ohiopowertool.com/p-444...Zv1DZ1CsFOaH9a-C4ktKr8Ti2jMhmK_ASABoCiJbw_wcB video of one in action..
Discuss this in the forum topic Concrete curb cuts: vertical or horizontal.