Finding OEM harness connectors?

I am starting a custom car wiring harness company, and I can't for the life of me find a resource that can tell me what the ECU connectors for a car are and link me to buy them. TE is a nightmare because there are so many connectors and no way to reliably sort them. Could I get some help? Ideally, both male and female housings with crimp on pins

I’m a professional electrical engineer and I’ve faced similar problems in my job (which has nothing to do with motor sports). But here is what I’ve done. Make some basic measurements of the pins and the connectors. A key metric is pin center to pin center (pin pitch) in mm. Start going through TE Connectivity’s website and sort on the pin pitch. You’ll find connectors organized into families or series with a ton of variants. Get familiar with the series of connectors you think might be a likely match. If you have a resale number and a website you should register with TE Connectivity as a business. Then submit a request (online) for applications support. The support engineers are usually pretty knowledgeable and may know exactly what you are looking for or will know if the ECU connector you are looking at is proprietary. Even if the initial guy doesn’t know he will connect you with an automotive specialist that will certainly know. Even though TE is a huge company they are used to working with small players. Unlikely they will blow you off. I don’t know about TE specifically, but if they use factory reps (independent sales guys) get in touch with your local rep. That is your ticket to almost endless free samples. Get one of everything and start a “reference library”. Try and order parts through the rep instead of Mouser or DigiKey so they know you are actually buying stuff.Good luck!