Been getting miles on my new Terry road bike and have always wanted to compete in cross.

Finding a bike in my size was already difficult. I have a 43cm Terry with 650c wheels and even during the fitting they had to jam the stem all the way down.

I ave a single speed I built up but I ended up giving to my brother because it was too big. It was a 49cm with 700c wheels with annoying toe overlap.

I have a old Schwinn Caliente that I converted years ago to a single speed because I got tired of the shifting not working. I used to commute on it until I got a new road bike recently. So now the Caliente is just sitting and in the garage so maybe it can be good to build a frankebike for cross? The bike as 24" wheels. Would I put 24" wheels or even be able to put 650b wheels on it? Would I have a disadvantage in racing (not that I care)? Would I have to get a new fork?

I suppose my other option is to look on CL and find a frame small enough for me and build up from there? It could be a fun project. I have heard that I should just find a mountain bike frame and do that instead of the Schwinn but they never told me why.

I probably won't have anyone to help me with this project since no one I knows enjoy bikes the same way I do. I honestly don't know where to start though, like what parts to get and what not.