Don't worry about being sacked - they would be extremely stupid to do so in the circumstances you have outlined.
If it can be proven that a decision was made BEFORE the hearing then it should be overturned as a matter of course. Although I would assume that it would be difficult to prove.
The 52 mile thing can be got round by your employer stating that they tried to protect your standing in the locale and decided to hold it somewhere you were not known so well.
Appeal against the decision AND the procedure. Organise yourself and get copies of the company's disciplinary and appeal procedure. Highlight for yourself the areas in which they did not follow the procedure.
From this and your previous post it seems as though the main areas are-
*Not giving you the required 7 days to prepare
*Not taking a statement and producing this to you from their main "witness"
*Not checking the reading on the electronic equipment that may have proven your innocence
*Making a decision before the hearing (if provable)
Also make clear the defence you had and that you did not feel that all the evidence that you provided was taken into consideration.
If at any time during the hearing you wish to take a break, regain your thoughts or check your notes then ask for a break. Don't let them dictate the meeting to you - it's your appeal.
Present yourself in a calm and professional manner and at all times be polite and courteous. Although this is your livelihood, try to take all emotion out of it.
Most of all - good luck.