I think the OP is missing a key issue here too in that the potential employee has to take an unprecedented risk to their own business and career, we have all seen those videos on youtube where a stupid act like a driving offense caught on dashcam by an employee can lose them their job and in some cases do irreversible damage to the company, it can takes yrs to decades to build up a company reputation and it can be sunk in a matter of minutes through a careless act. This isn't about the likelihood of reoffending here, this is one of those crimes that if it does get out could ruin a company simply by association.
The information the company has about the OP will need to be disclosed a number of times and will not only affect the type of work like domestic, industrial or commercial but also working with other trades, effectively if the company or any other company they work along side has say apprentices, work experience etc on site who can be as young as 14 and 15 then they may be required to put special measures in place like permanent supervision etc, even if measures could be implemented it is the court of public opinion that is the biggest risk to the company and the longer the OP is employed and the more times that this is disclosed the higher the likelihood of it been leaked out causing possible irreparable damage to the company.
It maybe the case the OP will never reoffend, it maybe the case the OP has served their time for the crime but the nature of the crime means it will not only weigh heavily on their shoulders for life but also puts a heavy burden on any potential employer especially ones where the job see's them interacting with the public on a regular basis regardless of the age.
My advice is if you want this type of career or similar is to look for employment where you effectively work in one identified environment like been the 'inhouse' electrician for say a factory etc, these types of jobs will not require your details to be submitted to anyone else other than your employee when you apply for the job and limitations and measures could be agreed beforehand between you both and as long as you abide by them then no one else needs to be the wiser giving you better prospects and job security.
I have deliberately kept away from my own views here and tried to give constructive advice, it is not for me as part of the forum to play judge and jury for a crime in your past which you have served your punishment on but I must in part reflect on the difficulties you may face and the risks that employers will be taking in employing you, hopefully I gave you direction that may see you get a career you want but as you are well aware, your options are limited so you have a much harder mountain to climb than most.