Surge protection will likely be ineffective if for any reason the earthing is deficient.
As an electrical engineer that deals with noise and earthing on industrial plant to a high level of detail, I really implore you to over engineer the earthing, or do not bother to proceed.
Earthing as a quality reveals itself in two ways - continuously on a day to day basis with noise, and intermittently/rarely under fault, surge or other unusual conditions, sometimes with catastrophic or even lethal outcomes.
If nothing else I imagine you have many much loved items of equipment. Regardless of any value, it would be a shame to learn that a better earth may have protected them or a family member the hard way.
As an electrical engineer that deals with noise and earthing on industrial plant to a high level of detail, I really implore you to over engineer the earthing, or do not bother to proceed.
Earthing as a quality reveals itself in two ways - continuously on a day to day basis with noise, and intermittently/rarely under fault, surge or other unusual conditions, sometimes with catastrophic or even lethal outcomes.
If nothing else I imagine you have many much loved items of equipment. Regardless of any value, it would be a shame to learn that a better earth may have protected them or a family member the hard way.