The 41-year-old dad was pronounced dead at the Big Church Festival at Wiston Park, near Steyning, on Friday afternoon after police were called to reports of a “large sign” falling.
Six other people were taken to hospital and organisers confirmed the festival had been brought “to a close”.
Mr Guanco worked at the Jesus Living Water Church in Eastbourne, which has since paid tribute.
The church described him as “a faithful servant of God, “a loving husband”, and a “devoted and caring father”.
It posted on Facebook: “His life, his faith, his love, and his service to God will never be forgotten.
“We take comfort in believing that he is now home with the Lord, free from suffering and resting in eternal glory.”
A GoFundMe page has since been set up to support Mr Guanco’s wife, daughter, and wider family, raising more than £50,000 at time of writing.
The page reads: “His life reflected humility, faith, love, compassion, and service. Through his ministry, kindness, prayers, and encouragement, he touched many lives. His passing is deeply felt by everyone who had the privilege of knowing him.
“Today, his family – his wife, daughter, parents, siblings, and loved ones – are facing an unimaginable loss.”
Friday’s incident has been reported to the Health and Safety Executive and the local authority.
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The Archbishop of Canterbury Dame Sarah Mullally previously said she was “sad and shocked” to hear the news.
She went on: “I pray for his family, friends and loved ones as they grieve. I pray for those receiving treatment, and the healthcare workers looking after them.
“And I pray too for the other festivalgoers, staff and event organisers as they come to terms with these tragic events.”
