Butchering my new bed

I got a quote for a tailor made mattress to fit my cabin. The old one has a join in the middle and although not uncomfortable for a holiday, it’s not really going to keep me comfy for six months aboard. The quote came back at nearly 700 quid and that hurt! A little research later and I ordered a Silent Night three zone foam mattress with memory foam top. I spoke to Silent Night and told them I planned to cut it down and they told me that cutting it would void the guarantee and that the mattress would fall apart as the layers are not glued together. I carried on anyway thinking I would just re glue it after I cut it and I’m glad I did because now I have a tailor made mattress that didn’t need glueing because despite what I was told, the mattress didn’t fall apart and is now perfect for the job. It was pretty easy to cut with a carving knife and back inside its knitted cover, it looks great so now I have a very comfy bed to get into to and extra 400 quid in my bank!!!