Dave, simplest and safest way to refit deep recesses spark plugs is to get yourself a short length (6-8”) of rubber or plastic straight hose where the internal diameter is sufficient that the plug ceramic is a push fit and hold the plug tight enough that it won’t fall out.
Use this as a plug ‘holder’ to insert and start the thread, it makes it most unlikely you will cross the threads as your hose will turn rather than the plug if it starts to get tight!
The hose can be used to screw to hand tight then you use your rubber insert type plug socket and extension to nip up the plug until it bottoms. I then also don’t use a torque wrench and give them a 1/8th turn and that’s it.
BR
Colin
