Here is my background: I was a high school teacher that transitioned into data science about 4 years ago. I've been a data scientist and software engineer for the past 3-4 years and made a pretty good career out of it, and am now managing a small team of analysts, data scientists, and data engineers myself. However, I'm realizing I'd like to do research, specifically within computer science and natural language processing for the rest of my career. It's something I'm constantly drawn to and passionate about, and something I spend my weekends doing reading textbooks anyways, and I feel like I've hit my limits within industry. I'd like to actually contribute new algorithms and architectures, specifically within NLP (natural language processing).
Here is my problem: I don't have formal research experience- no published papers, no internships at research labs. My BA was in History over 10 years ago. I've done research projects for my work as a data scientist and deployed machine learning models into production as a result of different statistical tests I've performed, but I'm pretty sure the academic world does not consider this "real research". I do have a Masters in Computer Science from Syracuse (and graduated with the top GPA from the program) and an MBA from UCLA, and have many research papers I wrote for my classes, but were never submitted for publishing and have ended up as more or less repositories on my Github profile. Even though I was in the business school at UCLA, I've taken almost a minors-worth of graduate and senior-level coursework in CS, and done pretty well grade-wise. I also moonlight as an adjunct professor teaching a graduate level NLP and text analytics course at a top 25 university. But no research experience. I know I can do research, because I've never been so passionate about interested in this topic - and at worst, if I can't actually do it, I need to find out.
Here's what I need help with: I've seen lots of posts on different forums asking "is research required for a top X program, etc." This is not one of them. I know I have to pay my dues. I know people put in countless hours of sweat and toil in research labs to earn the privilege to be admitted to a PhD program. I'm not asking to cut the line because somehow I have some random industry experience. I've saved up enough money to quit my job (if I need to) and self fund myself for an internship or volunteer position at a research lab somewhere. I just don't know where to start - how does a 32 year old begin to acquire research experience? Do I just start picking professors from websites that have similar interests to mine and cold emailing them asking if they have volunteeer opportunities? Do I look for some sort of post-bac program? Do I try to find some research opportunities at work and document those projects really well?
Any perspectives or advice would be extremely appreciated. Thanks in advance.