Need some help with unusual entry please

I am extremely eager to study the Access to HE in Engineering this September. I plan on continuing onto a Mechanical Engineering BEng degree. I am very passionate about mechanical engineering and I've always had a mind for it. Machinery, automobiles and just the way things work are very very interesting to me and it's something I'm just really passionate about, so I'm confident I'll do very well.
I do not have usual circumstances, I have been homeschooled, often while travelling, all my life. I have no academic qualifications as a result of this, however, I do have pretty good academical knowledge and a lot of life experience including a variety of jobs. I have been self-studying mathematics and I've got to a pretty good level, definitely above GSCE level, and I'm confident I'd be able to pass any relevant entry exams to access courses if there is such a thing So, I was wondering how that'd work out. I am a bit confused about where to start from. I've emailed bournville college with basically the same that's on here. I have a friend where I can stay in Worcester so it's a good location. I'm just a bit unsure about the GSCE part, as I don't have any, so I was thinking of doing them alongside the access to HE, but I'm not sure if I actually need them. Oh BTW any feedback on city and south college, bournville campus? I'm not bothered about social life and I won't be working so I have no commitments apart from college so I'll be able to do it completely full time.
Sorry for the scattered post