Odd Man
Thru Hiker
I ended up buying some heal wedges to put into my Altras. Achilles and calves were just starting to niggle and I've enough problems without causing new ones. I really want to try and get you to take the first step into running but realise it's none of my business. Having said that, if you do take the first step the next one is much easier.
Heel wedges help with ankle mobility, especially with limited dorsiflexion, which is why weightlifting shoes have high heels to help to get into a deeper squat. I suspect you probably have a limited squat position.
I worked on my ankle mobility for a couple of years and now I can sit on a full deep squat, and I'm no spring chicken. It just takes time and dedication. Like you said, step by step, and within one's own limits.