69 Barracuda dash help/opinions

In OEM form the bezel is/was not removed without instruments and housing. Some portion of the original housing is probably still in there supporting these aftermarket instruments and the climate controller. So the wiring is the big difference. OEM had 2 harness connectors on printed circuit boards, 2 wires bolted onto the amp gauge and a speedometer cable. With the steering column lowered, the entire assembly comes out barely far enough to tilt face downward, disconnect and reconnect. You might actually have more slack in your aftermarket wiring than Chrysler provided.