IMO you are more risk of the insurance company having issue with a local garage bolting your tank in.... come claim time. Can't really argue with the standard, manufacturer designed, tested and supplied system.... but your local garage?
Standard specification Vs local garage untested, modified vehicle? It's more plausible they could argue against the expertise, competence, design, test and suitability of both the supplier and installer IMO. That's the bigger "get out" opportunity.