Following on from our kitchen reno last year we finally got around to getting splashbacks made for behind the oven and sink (my wife wanted glass splashbacks, I wanted a mix of glass and tile put in by someone who knows what they're doing - we compromised and now I'm going to install glass splashbacks...).

Anywho, installing is pretty straight forward except most instructions rely on their being a bench for the splashback to rest on while the silicone is setting. We have a freestanding oven/hob so there is no bench to rest it on. One set of instructions mentions affixing some sort of support behind the oven to support the weight of the splashback. The splashback could sit on the spacers between the oven and wall but I'm worried that they may not hold the weight (plastic with metal screw) plus the oven gets moved every so often to clean around it. 

Does the support need to be permanent or only while the silicone is setting? If only temp I could screw in a support under it for a few days until its settled. Otherwise I will have to look for something low profile I can affix permanently. Thankfully there is bench behind the sink however being an old house the window sill it will be meeting is not exactly level (next challenge).

Thanks