Hi guys, I am just wondering if it is possible to replace and/or customize your vehicle's electrical parts like aircon switches, cluster gauges and wiring?

For example, the case is we have a very old vehicle 1992 model and the gauges are not working anymore, the aircon switch looks terrible and about to break, no stereo, wiring is in total mess, central lock is busted, power window is also about to breakdown.

Is it possible to replace electrical parts and custom fit it into the old vehicle? my primary concern right no would be the aircon switch and the cluster gauges. The current aircon switch I have is a lever type, can I replace it with a knob type from a different vehicle?

Lastly, I noticed that this old vehicle of ours has an OBD1 port but I am thinking this port is not compatible with the OBD2 bluetooth connector I have but has anyone tried connecting an old OBD1 port to a bluetooth connector? Because if this is possible, I can simply replace the gauges with an android app if the OBD1 can be connected to bluetooth receiver.

Thanks for any replies!