Hi Mid-life pilot,
Congratulations on your decision, remember perseverance pays off!
Just thought I would add my thoughts as I have been in a somewhat similar position to you.
To re-iterate the other members posts, definitely get your class 1 medical squared away first. You can't proceed to your end goal without it.
I seriously would not bother with the Glasgow Nautical college. I thought, as it was close to home it would be easier etc. It wasn't and the course is really a waste of time. GO TO BRISTOL. They have the best notes, the best instructors and with the online QB and some dedicated study you will pass. The exams are not really that difficult.
Follow dfspilots' checklist.
A positve attitude (which its sounds like you have got!) is important because the process is long and somedays are completely Sh*te!
Maintain the big picture.
All the best
Curves